@article{tandonnet_krsticevic_basika_papathanos_torres_scott_2023, title={A chromosomal-scale reference genome of the New World Screwworm, Cochliomyia hominivorax}, volume={30}, ISSN={["1756-1663"]}, DOI={10.1093/dnares/dsac042}, abstractNote={The New World Screwworm, Cochliomyia hominivorax (Calliphoridae), is the most important myiasis-causing species in America. Screwworm myiasis is a zoonosis that can cause severe lesions in livestock, domesticated and wild animals, and occasionally in people. Beyond the sanitary problems associated with this species, these infestations negatively impact economic sectors, such as the cattle industry. Here, we present a chromosome-scale assembly of C. hominivorax's genome, organized in 6 chromosome-length and 515 unplaced scaffolds spanning 534 Mb. There was a clear correspondence between the D. melanogaster linkage groups A-E and the chromosomal-scale scaffolds. Chromosome quotient (CQ) analysis identified a single scaffold from the X chromosome that contains most of the orthologs of genes that are on the D. melanogaster fourth chromosome (linkage group F or dot chromosome). CQ analysis also identified potential X and Y unplaced scaffolds and genes. Y-linkage for selected regions was confirmed by PCR with male and female DNA. Some of the long chromosome-scale scaffolds include Y-linked sequences, suggesting misassembly of these regions. These resources will provide a basis for future studies aiming at understanding the biology and evolution of this devastating obligate parasite.}, number={1}, journal={DNA RESEARCH}, author={Tandonnet, Sophie and Krsticevic, Flavia and Basika, Tatiana and Papathanos, Philippos A. and Torres, Tatiana T. and Scott, Maxwell J.}, year={2023}, month={Feb} }
 @article{yamamoto_yadav_scott_2022, title={Evaluation of Additional Drosophila suzukii Male-Only Strains Generated Through Remobilization of an FL19 Transgene}, volume={10}, ISSN={["2296-4185"]}, DOI={10.3389/fbioe.2022.829620}, abstractNote={Drosophila suzukii (D. suzukii) (Matsumura, 1931; Diptera: Drosophilidae), also known as spotted wing Drosophila, is a worldwide pest of fruits with soft skins such as blueberries and cherries. Originally from Asia, D. suzukii is now present in the Americas and Europe and has become a significant economic pest. Growers largely rely on insecticides for the control of D. suzukii. Genetic strategies offer a species-specific environmentally friendly way for suppression of D. suzukii populations. We previously developed a transgenic strain of D. suzukii that produced only males on a diet that did not contain tetracycline. The strain carried a single copy of the FL19 construct on chromosome 3. Repeated releases of an excess of FL19 males led to suppression of D. suzukii populations in laboratory cage trials. Females died as a consequence of overexpression of the tetracycline transactivator (tTA) and tTA-activated expression of the head involution defective proapoptotic gene. The aim of this study was to generate additional male-only strains that carried two copies of the FL19 transgene through crossing the original line with a piggyBac jumpstarter strain. Males that carried either two chromosome 3 or a singleX-linked transgene were identified through stronger expression of the red fluorescent protein marker gene. The brighter fluorescence of the X-linked lines was likely due to dosage compensation of the red fluorescent protein gene. In total, four X-linked lines and eleven lines with two copies on chromosome 3 were obtained, of which five were further examined. All but one of the strains produced only males on a diet without tetracycline. When crossed with wild type virgin females, all of the five two copy autosomal strains examined produced only males. However, the single copy X-linked lines did not show dominant female lethality. Five of the autosomal lines were further evaluated for productivity (egg to adult) and male competition. Based on these results, the most promising lines have been selected for future population suppression experiments with strains from different geographical locations.}, journal={FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY}, author={Yamamoto, Akihiko and Yadav, Amarish K. and Scott, Maxwell J.}, year={2022}, month={Mar} }
 @article{li_yamamoto_belikoff_berger_griffith_scott_2021, title={A conditional female lethal system for genetic suppression of the global fruit crop pest Drosophila suzukii}, ISSN={["1526-4998"]}, DOI={10.1002/ps.6530}, abstractNote={BACKGROUND Drosophila suzukii (Matsumura, 1931, Diptera: Drosophilidae) is a global pest of soft-skinned fruits such as blueberries, cherries and raspberries. Also known as spotted-wing drosophila, D. suzukii is native to Asia but is now widely distributed in the Americas and Europe, and presents a serious challenge for growers. Genetic control strategies offer an environmentally friendly approach for the control of D. suzukii. RESULTS In this study, we developed transgenic strains of D. suzukii that carry dominant conditional female lethal transgenes. When raised in the absence of tetracycline, female D. suzukii die. We show that repeated releases of an excess of transgenic males can suppress D. suzukii populations in laboratory cage trials. CONCLUSION Our data suggest that the transgenic strain could provide an effective approach for control of this invasive pest of soft-skinned fruits.}, journal={PEST MANAGEMENT SCIENCE}, author={Li, Fang and Yamamoto, Akihiko and Belikoff, Esther J. and Berger, Amy and Griffith, Emily H. and Scott, Maxwell J.}, year={2021}, month={Jul} }
 @article{williamson_yan_scott_2021, title={Conditional knockdown of transformer in sheep blow fly suggests a role in repression of dosage compensation and potential for population suppression}, volume={17}, ISSN={["1553-7404"]}, DOI={10.1371/journal.pgen.1009792}, abstractNote={The transformer ( tra ) gene is essential for female development in many insect species, including the Australian sheep blow fly, Lucilia cuprina . Sex-specific tra RNA splicing is controlled by Sex lethal ( Sxl ) in Drosophila melanogaster but is auto-regulated in L . cuprina . Sxl also represses X chromosome dosage compensation in female D . melanogaster . We have developed conditional Lctra RNAi knockdown strains using the tet-off system. Four strains did not produce females on diet without tetracycline and could potentially be used for genetic control of L . cuprina . In one strain, which showed both maternal and zygotic tTA expression, most XX transformed males died at the pupal stage. RNAseq and qRT-PCR analyses of mid-stage pupae showed increased expression of X-linked genes in XX individuals. These results suggest that Lctra promotes somatic sexual differentiation and inhibits X chromosome dosage compensation in female L . cuprina . However, XX flies homozygous for a loss-of-function Lctra knockin mutation were fully transformed and showed high pupal eclosion. Two of five X-linked genes examined showed a significant increase in mRNA levels in XX males. The stronger phenotype in the RNAi knockdown strain could indicate that maternal Lctra expression may be essential for initiation of dosage compensation suppression in female embryos.}, number={10}, journal={PLOS GENETICS}, author={Williamson, Megan E. and Yan, Ying and Scott, Maxwell J.}, year={2021}, month={Oct} }
 @article{paulo_junqueira_arp_vieira_ceballos_skoda_perez-de-leon_sagel_mcmillan_scott_et al._2021, title={Disruption of the odorant coreceptor Orco impairs foraging and host finding behaviors in the New World screwworm fly}, volume={11}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-021-90649-x}, abstractNote={Abstract The evolution of obligate ectoparasitism in blowflies (Diptera: Calliphoridae) has intrigued scientists for over a century, and surprisingly, the genetics underlying this lifestyle remain largely unknown. Blowflies use odors to locate food and oviposition sites; therefore, olfaction might have played a central role in niche specialization within the group. In insects, the coreceptor Orco is a required partner for all odorant receptors (ORs), a major gene family involved in olfactory-evoked behaviors. Hence, we characterized the Orco gene in the New World screwworm, Cochliomyia hominivorax , a blowfly that is an obligate ectoparasite of warm-blooded animals. In contrast, most of the closely related blowflies are scavengers that lay their eggs on dead animals. We show that the screwworm Orco orthologue ( ChomOrco ) is highly conserved within Diptera, showing signals of strong purifying selection. Expression of ChomOrco is broadly detectable in chemosensory appendages, and is related to morphological, developmental, and behavioral aspects of the screwworm biology. We used CRISPR/Cas9 to disrupt ChomOrco and evaluate the consequences of losing the OR function on screwworm behavior. In two-choice assays, Orco mutants displayed an impaired response to floral-like and animal host-associated odors, suggesting that OR-mediated olfaction is involved in foraging and host-seeking behaviors in C . hominivorax . These results broaden our understanding of the chemoreception basis of niche occupancy by blowflies.}, number={1}, journal={SCIENTIFIC REPORTS}, author={Paulo, Daniel F. and Junqueira, Ana C. M. and Arp, Alex P. and Vieira, Andre S. and Ceballos, Jorge and Skoda, Steven R. and Perez-de-Leon, Adalberto A. and Sagel, Agustin and McMillan, William O. and Scott, Maxwell J. and et al.}, year={2021}, month={May} }
 @misc{tait_mermer_stockton_lee_avosani_abrieux_anfora_beers_biondi_burrack_et al._2021, title={Drosophila suzukii (Diptera: Drosophilidae): A Decade of Research Towards a Sustainable Integrated Pest Management Program}, volume={114}, ISSN={["1938-291X"]}, DOI={10.1093/jee/toab158}, abstractNote={Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD control programs rely heavily on insecticides, exceedance of maximum residue levels (MRLs) has also resulted in crop rejections. The economic impact of SWD has been particularly severe for organic operations, mainly due to the limited availability of effective insecticides. Integrated pest management (IPM) of SWD could significantly reduce chemical inputs but would require substantial changes to horticultural management practices. This review evaluates the most promising methods studied as part of an IPM strategy against SWD across the world. For each of the considered techniques, the effectiveness, impact, sustainability, and stage of development are discussed.}, number={5}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Tait, Gabriella and Mermer, Serhan and Stockton, Dara and Lee, Jana and Avosani, Sabina and Abrieux, Antoine and Anfora, Gianfranco and Beers, Elizabeth and Biondi, Antonio and Burrack, Hannah and et al.}, year={2021}, month={Oct}, pages={1950–1974} }
 @article{davis_belikoff_dickey_scholl_benoit_scott_2021, title={Genome and transcriptome sequencing of the green bottle fly, Lucilia sericata, reveals underlying factors of sheep flystrike and maggot debridement therapy}, volume={113}, ISSN={["1089-8646"]}, DOI={10.1016/j.ygeno.2021.10.003}, abstractNote={The common green bottle blow fly Lucilia sericata (family, Calliphoridae) is widely used for maggot debridement therapy, which involves the application of sterile maggots to wounds. The larval excretions and secretions are important for consuming necrotic tissue and inhibiting bacterial growth in wounds of patients. Lucilia sericata is also of importance as a pest of sheep and in forensic studies to estimate a postmortem interval. Here we report the assembly of a 565.3 Mb genome from long read PacBio DNA sequencing of genomic DNA. The genome contains 14,704 predicted protein coding genes and 1709 non-coding genes. Targeted annotation and transcriptional analyses identified genes that are highly expressed in the larval salivary glands (secretions) and Malpighian tubules (excretions) under normal growth conditions and following heat stress. The genomic resources will underpin future genetic studies and in development of engineered strains for genetic control of L. sericata and for biotechnology-enhanced maggot therapy.}, number={6}, journal={GENOMICS}, author={Davis, Rebecca J. and Belikoff, Esther J. and Dickey, Allison N. and Scholl, Elizabeth H. and Benoit, Joshua B. and Scott, Maxwell J.}, year={2021}, month={Nov}, pages={3978–3988} }
 @article{scott_2021, title={Sex Determination and Dosage Compensation: femaleless Is the Link in Anopheles Mosquitoes}, volume={31}, ISSN={["1879-0445"]}, DOI={10.1016/j.cub.2021.01.078}, abstractNote={A new study finds that the femaleless gene is essential for sexual development and repression of X-chromosome dosage compensation in the malaria vector Anopheles gambiae. This could provide the basis for a new genetic approach to control this pest. A new study finds that the femaleless gene is essential for sexual development and repression of X-chromosome dosage compensation in the malaria vector Anopheles gambiae. This could provide the basis for a new genetic approach to control this pest. In the most widely accepted view, sex chromosomes evolved from a pair of autosomes. Due to a lack of recombination, the sex-specific chromosome (for example, the Y chromosome) degenerates over time with the exception of the sex-determining gene and closely linked loci. This leads to a problem in gene balance as there are twice as many copies of the partner chromosome (X chromosome in this example) in one sex compared to the other. Consequently, organisms evolved genetic mechanisms for compensating differences in the number of copies of the X chromosome1Charlesworth B. The evolution of chromosomal sex determination and dosage compensation.Curr. Biol. 1996; 6: 149-162Abstract Full Text Full Text PDF PubMed Scopus (381) Google Scholar. In the fly Drosophila melanogaster, the Y chromosome has few genes and plays no role in sex determination or dosage compensation. Rather, an X-chromosome-counting mechanism determines sex and regulates X-chromosome dosage compensation through activation of the Sex lethal (Sxl) gene in XX embryos. In a well characterized genetic regulatory hierarchy, Sxl represses X-chromosome dosage compensation and activates female development through control of expression of the male specific lethal 2 (msl2) and transformer (tra) genes, respectively2Cline T.W. Meyer B.J. Vive la difference: males vs females in flies vs worms.Annu. Rev. Genet. 1996; 30: 637-702Crossref PubMed Scopus (478) Google Scholar. In other species, different genes determine sex, such as Y-linked male-determining factors in the medfly (Ceratitis capitata) and housefly (Musca domestica)3Meccariello A. Salvemini M. Primo P. Hall B. Koskinioti P. Dalikova M. Gravina A. Gucciardino M.A. Forlenza F. Gregoriou M.E. et al.Maleness-on-the-Y (MoY) orchestrates male sex determination in major agricultural fruit fly pests.Science. 2019; 365: 1457-1460Crossref PubMed Scopus (44) Google Scholar,4Sharma A. Heinze S.D. Wu Y. Kohlbrenner T. Morilla I. Brunner C. Wimmer E.A. van de Zande L. Robinson M.D. Beukeboom L.W. et al.Male sex in houseflies is determined by Mdmd, a paralog of the generic splice factor gene CWC22.Science. 2017; 356: 642-645Crossref PubMed Scopus (63) Google Scholar. However, it was not clear if there were any other examples of genes that, like Sxl, control both female development and X-chromosome expression. In this issue of Current Biology, Krzywinska and colleagues show that, in the malaria vector Anopheles gambiae, femaleless (fle) acts in females to control sexual development and repress X-chromosome dosage compensation5Krzywinska E. Ferretti L. Li J. Li J.-C. Chen C.-H. Krzywinski J. femaleless controls sex determination and dosage compensation pathways in females of the Anopheles mosquitoes.Curr. Biol. 2021; 31: 1084-1091Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar. The D. melanogaster SXL protein contains two RRM RNA binding domains and binds preferentially to polyU sequences6Penalva L.O. Sanchez L. RNA binding protein sex-lethal (Sxl) and control of Drosophila sex determination and dosage compensation.Microbiol. Mol. Biol. Rev. 2003; 67: 343-359Crossref PubMed Scopus (124) Google Scholar. SXL regulates the RNA splicing of tra transcripts through binding to and blocking use of the default splice acceptor site that is used in males. As a consequence, only the female tra transcript encodes a functional protein. SXL regulates its own splicing through a similar mechanism of blocking the use of the default splice acceptor site that is used in males. The autoregulatory mechanism is initiated through a brief burst of Sxl transcription in female embryos by X-chromosome-counting factors. SXL represses X-chromosome dosage compensation through binding to sites in the 5’ and 3’ UTRs of msl2 RNA and thereby blocking translation. MSL2 is one of five proteins that form the MSL complex in males along with the long noncoding roX1 and roX2 RNAs7Kuroda M.I. Hilfiker A. Lucchesi J.C. Dosage compensation in Drosophila-a model for the coordinate regulation of transcription.Genetics. 2016; 204: 435-450Crossref PubMed Scopus (36) Google Scholar. The MSL complex is responsible for doubling the transcription of X-linked genes in males. TRA, together with Transformer2 (TRA2) and RBP1, regulates the splicing of transcripts for the doublesex (dsx) and fruitless genes (fru)6Penalva L.O. Sanchez L. RNA binding protein sex-lethal (Sxl) and control of Drosophila sex determination and dosage compensation.Microbiol. Mol. Biol. Rev. 2003; 67: 343-359Crossref PubMed Scopus (124) Google Scholar. DSX and FRU are highly conserved DNA-binding proteins that together control the expression of genes required for sexual development and behavior8Clough E. Jimenez E. Kim Y.A. Whitworth C. Neville M.C. Hempel L.U. Pavlou H.J. Chen Z.X. Sturgill D. Dale R.K. et al.Sex- and tissue-specific functions of Drosophila doublesex transcription factor target genes.Dev. Cell. 2014; 31: 761-773Abstract Full Text Full Text PDF PubMed Scopus (69) Google Scholar,9Neville M.C. Nojima T. Ashley E. Parker D.J. Walker J. Southall T. Van de Sande B. Marques A.C. Fischer B. Brand A.H. et al.Male-specific fruitless isoforms target neurodevelopmental genes to specify a sexually dimorphic nervous system.Curr. Biol. 2014; 24: 229-241Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar. The TRA/TRA2/RBP1 complex binds to a 13-nucleotide motif that is present in multiple copies in the dsx and fru transcripts. The female and male dsx transcripts share the common exons that encode the DNA-binding domain but differ at their 3’ ends. In the female dsx transcript, the so-called TRA/TRA2 sites are found in the 3’ UTR. Binding of the TRA/TRA2/RBP1 complex to these sites enhances the use of a nearby, weak splice-acceptor site that is otherwise ignored by the splicing apparatus. In males, the female-specific exon is skipped, and the last common exon is spliced to a downstream male-specific exon. In his influential and prophetic essay, Adam Wilkins proposed that sex-determination genetic pathways evolved from the bottom up with the final step added first and the top added last10Wilkins A.S. Moving up the hierarchy: a hypothesis on the evolution of a genetic sex determination pathway.Bioessays. 1995; 17: 71-77Crossref PubMed Scopus (242) Google Scholar. His hypothesis has proved to be largely correct in insects. The genes at the bottom of the pathway, dsx and fru, regulate sexual development and behavior in a wide range of insect species11Bopp D. Saccone G. Beye M. Sex determination in insects: variations on a common theme.Sex. Dev. 2014; 8: 20-28Crossref PubMed Scopus (79) Google Scholar. In addition, the master gene at the top of the D. melanogaster pathway, Sxl appears to have no role in sex determination in species other than D. melanogaster and its close relatives. Rather, in many other Diptera, such as the Australian sheep blow fly (Lucilia cuprina) and the medfly, sex is determined by a Y-linked male-determining gene. What about the middle of the pathway? In sheep blowfly, medfly and housefly, the TRA/TRA2 complex regulates dsx and fru splicing much as in D. melanogaster. tra transcripts are sex-specifically spliced but, unlike in D. melanogaster, splicing is autoregulated with multiple TRA/TRA2 sites in the first female intron. It is not clear how tra splicing is regulated by the male-determining factor(s). But it is not only Diptera: tra determines sex in a wide range of insects including the honeybee, the beetle Tribolium castaneum and the wasp Nasonia vitripennis11Bopp D. Saccone G. Beye M. Sex determination in insects: variations on a common theme.Sex. Dev. 2014; 8: 20-28Crossref PubMed Scopus (79) Google Scholar. So, it has been a major surprise that orthologs of tra have not been identified in mosquito genomes, including the well-annotated An. gambiae genome. However, the top of the pathway in An. gambiae has been identified. The Y-linked Yob gene controls the male-specific splicing of the dsx and fru transcripts12Krzywinska E. Dennison N.J. Lycett G.J. Krzywinski J. A maleness gene in the malaria mosquito Anopheles gambiae.Science. 2016; 353: 67-69Crossref PubMed Scopus (63) Google Scholar (Figure 1). Interestingly, Yob RNA encodes a short 56-amino acid protein. In medfly, the Y-linked male-determining gene MoY also encodes a short protein of 70 amino acids3Meccariello A. Salvemini M. Primo P. Hall B. Koskinioti P. Dalikova M. Gravina A. Gucciardino M.A. Forlenza F. Gregoriou M.E. et al.Maleness-on-the-Y (MoY) orchestrates male sex determination in major agricultural fruit fly pests.Science. 2019; 365: 1457-1460Crossref PubMed Scopus (44) Google Scholar. Although it was possible that Yob somehow directly regulated dsx and fru RNA splicing, Krzywinska et al.5Krzywinska E. Ferretti L. Li J. Li J.-C. Chen C.-H. Krzywinski J. femaleless controls sex determination and dosage compensation pathways in females of the Anopheles mosquitoes.Curr. Biol. 2021; 31: 1084-1091Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar searched for a splicing factor that could be an intermediate in the regulatory pathway. They first identified An. gambiae proteins that showed similarity to D. melanogaster TRA2. RNAi-knockdown experiments in a female cell line were then performed to determine if any of the candidates were required for female-specific dsx splicing. They came up empty with the top two candidates but struck gold with the third, which was renamed femaleless (fle). Transfections with double stranded fle RNA caused a decrease in female-specific dsx transcripts and the appearance of male-specific ones. Interestingly, dsx and fru RNAs both contain multiple copies of a CAAUCAA motif that resembles part of a D. melanogaster TRA/TRA2 site and could potentially be FLE binding sites. The authors then went on to make several transgenic An. gambiae strains that constitutively express three short fle dsRNAs to knockdown fle expression. The degree of knockdown and phenotype varied between the lines due to position effects. However, most of the lines that produced viable females showed clear masculinization. At the RNA level, fle is equally expressed in males and females. This raises the question of how fle is repressed in males? It is possible that fle is a direct target of Yob, which both determines sex and is required for X-chromosome dosage compensation in males12Krzywinska E. Dennison N.J. Lycett G.J. Krzywinski J. A maleness gene in the malaria mosquito Anopheles gambiae.Science. 2016; 353: 67-69Crossref PubMed Scopus (63) Google Scholar. Alternatively, fle alone could be insufficient in females but act together with a yet to be discovered female-specific protein (Figure 1). What about X-chromosome dosage compensation? An. gambiae has a large X chromosome with over 1,000 genes, and X-chromosome gene expression is dosage compensated13Rose G. Krzywinska E. Kim J. Revuelta L. Ferretti L. Krzywinski J. Dosage compensation in the African malaria mosquito Anopheles gambiae.Genome Biol. Evol. 2016; 8: 411-425PubMed Google Scholar. As you might gather from the gene name femaleless, the phenotype of the strongest fle knockdown lines was not masculinization but female-specific lethality. This of course is reminiscent of the phenotype of Sxl mutants in D. melanogaster2Cline T.W. Meyer B.J. Vive la difference: males vs females in flies vs worms.Annu. Rev. Genet. 1996; 30: 637-702Crossref PubMed Scopus (478) Google Scholar. RNAseq analysis confirmed that X-chromosome gene expression is significantly upregulated in fle-knockdown females. Thus, fle appears to both repress dosage compensation and promote sexual development in females. A number of questions are raised by this research. How does fle repress dosage compensation in females? Does Yob activate dosage compensation in males? For that matter, what is the mechanism of X-chromosome dosage compensation in An. gambiae? Could dosage compensation be mediated by the MSL complex as in D. melanogaster? The genes that comprise the An. gambiae X chromosome largely map to the D. melanogaster X chromosome13Rose G. Krzywinska E. Kim J. Revuelta L. Ferretti L. Krzywinski J. Dosage compensation in the African malaria mosquito Anopheles gambiae.Genome Biol. Evol. 2016; 8: 411-425PubMed Google Scholar. Are there factors in other insects that, like fle and Sxl, regulate both X-chromosome dosage compensation and sex determination? In the sheep blowfly, the largely heterochromatic X chromosome has few genes, but they are dosage compensated14Linger R.J. Belikoff E.J. Scott M.J. Dosage compensation of X-Linked Muller element F genes but not X-linked transgenes in the Australian sheep blowfly.PLoS One. 2015; 10: e0141544Crossref PubMed Scopus (14) Google Scholar. The genes on the L. cuprina X chromosome map to the D. melanogaster fourth chromosome, which is thought to be the ancestral X chromosome in Diptera. The no blokes (nbl) gene was found to be essential for male viability and normal X-chromosome expression in L. cuprina15Davis R.J. Belikoff E.J. Scholl E.H. Li F. Scott M.J. no blokes is essential for male viability and X chromosome gene expression in the Australian sheep blowfly.Curr. Biol. 2018; 28: 1987-1992Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar, and like fle, nbl RNA is expressed in both sexes. Perhaps there is a gene to be found that, like fle, represses X-chromosome hyperactivation in females. As the authors note, a conditional fle knockdown strain could be used to produce a male-only population for genetic control of this major pest. The genetic makeup of the strain could be similar to male-only strains developed for other insect pests16Yan Y. Linger R.J. Scott M.J. Building early-larval sexing systems for genetic control of the Australian sheep blow fly Lucilia cuprina using two constitutive promoters.Sci. Rep. 2017; 7: 2538Crossref PubMed Scopus (17) Google Scholar. For example, a two-component strain with one component being the tetracycline transactivator (tTA) driven by a moderate constitutive promoter and the second component consisting of a tTA-regulated fle dsRNA gene construct such as used in the current study5Krzywinska E. Ferretti L. Li J. Li J.-C. Chen C.-H. Krzywinski J. femaleless controls sex determination and dosage compensation pathways in females of the Anopheles mosquitoes.Curr. Biol. 2021; 31: 1084-1091Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar. In the absence of tetracycline, induction of fle dsRNA expression by tTA would lead to female lethality. Area-wide releases of fertile17Vella M.R. Gould F. Lloyd A.L. Mathematical modeling of genetic pest management through female-specific lethality: Is one locus better than two?.bioRxiv. 2020; https://doi.org/10.1101/2020.04.06.028738Crossref Scopus (0) Google Scholar or radiation-sterilized males could lead to suppression of this important malaria vector. Alternatively, fle could be a target of a homing gene drive for population suppression, analogous to the An. gambiae drive strain that targets the dsx female exon18Kyrou K. Hammond A.M. Galizi R. Kranjc N. Burt A. Beaghton A.K. Nolan T. Crisanti A. A CRISPR-Cas9 gene drive targeting doublesex causes complete population suppression in caged Anopheles gambiae mosquitoes.Nat. Biotechnol. 2018; 36: 1062-1066Crossref PubMed Scopus (305) Google Scholar.}, number={5}, journal={CURRENT BIOLOGY}, author={Scott, Max}, year={2021}, month={Mar}, pages={R260–R263} }
 @article{webster_scott_2021, title={The Aedes aegypti (Diptera: Culicidae) hsp83 Gene Promoter Drives Strong Ubiquitous DsRed and ZsGreen Marker Expression in Transgenic Mosquitoes}, volume={58}, ISSN={["1938-2928"]}, DOI={10.1093/jme/tjab128}, abstractNote={Transgenic strains of the mosquito disease vector Aedes aegypti (L.) are being developed for population suppression or modification. Transgenic mosquitoes are identified using fluorescent protein genes. Here we describe DsRed and ZsGreen marker genes driven by the constitutive Ae. aegypti heat shock protein 83 (hsp83) promoter in transgenic mosquitoes. Transgenic larvae and pupae show strong full body expression of the red and green fluorescent proteins. This greatly assists in screening for transgenic individuals while making new or maintaining already established lines. Transient marker gene expression after embryo microinjection was readily visible in developing larvae allowing the separation of individuals that are more likely to produce transgenic offspring. The strongly expressed marker genes developed in this study should facilitate the detection of transgenic Ae. aegypti larvae or pupae in the field.}, number={6}, journal={JOURNAL OF MEDICAL ENTOMOLOGY}, author={Webster, Sophia H. and Scott, Maxwell J.}, year={2021}, month={Nov}, pages={2533–2537} }
 @article{concha_yan_arp_quilarque_sagel_leon_owen mcmillan_skoda_scott_2020, title={An early female lethal system of the New World screwworm, Cochliomyia hominivorax, for biotechnology-enhanced SIT}, volume={21}, ISSN={["1471-2156"]}, DOI={10.1186/s12863-020-00948-x}, abstractNote={Abstract Background The New World Screwworm fly (NWS), Cochliomyia hominivorax , is an ectoparasite of warm-blooded animals and a major pest of livestock in parts of South America and the Caribbean where it remains endemic. In North and Central America it was eradicated using the Sterile Insect Technique (SIT). A control program is managed cooperatively between the governments of the United States and Panama to prevent the northward spread of NWS from infested countries in South America. This is accomplished by maintaining a permanent barrier through the release of millions of sterile male and female flies in the border between Panama and Colombia. Our research team demonstrated the utility of biotechnology-enhanced approaches for SIT by developing a male-only strain of the NWS. The strain carried a single component tetracycline repressible female lethal system where females died at late larval/pupal stages. The control program can be further improved by removing females during embryonic development as larval diet costs are significant. Results The strains developed carry a two-component system consisting of the Lucilia sericata bottleneck gene promoter driving expression of the tTA gene and a tTA-regulated Lshid proapoptotic effector gene. Insertion of the sex-specifically spliced intron from the C. hominivorax transformer gene within the Lshid gene ensures that only females die when insects are reared in the absence of tetracycline. In several double homozygous two-component strains and in one “All-in-one” strain that had both components in a single construct, female lethality occurred at the embryonic and/or first instar larval stages when raised on diet without tetracycline. Laboratory evaluation for phenotypes that are relevant for mass rearing in a production facility revealed that most strains had fitness characteristics similar to the wild type J06 strain that is currently reared for release in the permanent barrier. Testing of an “All in one” strain under mass rearing conditions showed that the strain maintained the fitness characteristics observed in small-scale rearing. Conclusions The early female lethal strains described here could be selected by the NWS Control Program for testing at large scale in the production facility to enhance the efficiency of the NWS eradication program.}, journal={BMC GENETICS}, author={Concha, Carolina and Yan, Ying and Arp, Alex and Quilarque, Evelin and Sagel, Agustin and Leon, Adalberto Perez and Owen McMillan, W. and Skoda, Steven and Scott, Maxwell J.}, year={2020}, month={Dec} }
 @article{yan_scott_2020, title={Building a transgenic sexing strain for genetic control of the Australian sheep blow fly Lucilia cuprina using two lethal effectors}, volume={21}, ISSN={["1471-2156"]}, DOI={10.1186/s12863-020-00947-y}, abstractNote={Abstract Background The sterile insect technique (SIT) has been successfully used in many pest management programs worldwide. Some SIT programs release both sexes due to the lack of genetic sexing strains or efficient sex separation methods but sterile females are ineffective control agents. Transgenic sexing strains (TSS) using the tetracycline-off control system have been developed in a variety of insect pests, from which females die by either of two commonly used lethal effectors: overexpression of the transcription factor tetracycline transactivator (tTA) or ectopic expression of a proapoptotic gene, such as head involution defective ( hid ). The lethality from tTA overexpression is thought to be due to “transcriptional squelching”, while hid causes lethality by induction of apoptosis. This study aims to create and characterize a TSS of Lucilia cuprina , which is a major pest of sheep, by combining both lethal effectors in a single transgenic strain. Results Here a stable TSS of L. cuprina (DH6) that carries two lethal effectors was successfully generated, by crossing FL3#2 which carries a female-specific tTA overexpression cassette, with EF1#12 which carries a tTA-regulated Lshid Ala2 cassette. Females with one copy of the FL3#2 transgene are viable but up to 99.8% of homozygous females die at the pupal stage when raised on diet that lacks tetracycline. Additionally, the female lethality of FL3#2 was partially repressed by supplying tetracycline to the parental generation. With an additional Lshid Ala2 effector, the female lethality of DH6 is 100% dominant and cannot be repressed by maternal tetracycline. DH6 females die at the late-larval stage. Several fitness parameters important for mass rearing such as hatching rate, adult emergence and sex ratio were comparable to those of the wild type strain. Conclusions Compared to the parental FL3#2 strain, the DH6 strain shows stronger female lethality and lethality occurs at an earlier stage of development. The combination of two tTA-dependent lethal effectors could improve strain stability under mass rearing and could reduce the risk of resistance in the field if fertile males are released. Our approach could be easily adapted for other pest species for an efficient, safe and sustainable genetic control program.}, journal={BMC GENETICS}, author={Yan, Ying and Scott, Maxwell J.}, year={2020}, month={Dec} }
 @article{scott_benoit_davis_bailey_varga_martinson_hickner_syed_cardoso_torres_et al._2020, title={Genomic analyses of a livestock pest, the New World screwworm, find potential targets for genetic control programs}, volume={3}, ISSN={["2399-3642"]}, DOI={10.1038/s42003-020-01152-4}, abstractNote={Abstract The New World Screwworm fly, Cochliomyia hominivorax , is a major pest of livestock in South America and Caribbean. However, few genomic resources have been available for this species. A genome of 534 Mb was assembled from long read PacBio DNA sequencing of DNA from a highly inbred strain. Analysis of molecular evolution identified 40 genes that are likely under positive selection. Developmental RNA-seq analysis identified specific genes associated with each stage. We identify and analyze the expression of genes that are likely important for host-seeking behavior (chemosensory), development of larvae in open wounds in warm-blooded animals (heat shock protein, immune response) and for building transgenic strains for genetic control programs including gene drive (sex determination, germline). This study will underpin future experiments aimed at understanding the parasitic lifestyle of the screwworm fly and greatly facilitate future development of strains for efficient systems for genetic control of screwworm.}, number={1}, journal={COMMUNICATIONS BIOLOGY}, author={Scott, Maxwell J. and Benoit, Joshua B. and Davis, Rebecca J. and Bailey, Samuel T. and Varga, Virag and Martinson, Ellen O. and Hickner, Paul V and Syed, Zainulabeuddin and Cardoso, Gisele A. and Torres, Tatiana T. and et al.}, year={2020}, month={Aug} }
 @article{yan_williamson_davis_andere_picard_scott_2020, title={Improved transgenic sexing strains for genetic control of the Australian sheep blow fly Lucilia cuprina using embryo-specific gene promoters}, volume={295}, ISSN={["1617-4623"]}, DOI={10.1007/s00438-019-01622-3}, number={2}, journal={MOLECULAR GENETICS AND GENOMICS}, author={Yan, Ying and Williamson, Megan E. and Davis, Rebecca J. and Andere, Anne A. and Picard, Christine J. and Scott, Maxwell J.}, year={2020}, month={Mar}, pages={287–298} }
 @article{hickner_mittapalli_subramoniam_sagel_watson_scott_arp_leon_syed_2020, title={Physiological and molecular correlates of the screwworm fly attraction to wound and animal odors}, volume={10}, ISBN={2045-2322}, DOI={10.1038/s41598-020-77541-w}, abstractNote={Abstract The screwworm fly, Cochliomyia hominivorax (Coquerel), was successfully eradicated from the United States by the sterile insect technique (SIT). However, recent detection of these flies in the Florida Keys, and increased risk of introductions to the other areas warrant novel tools for management of the flies. Surveillance, a key component of screwworm control programs, utilizes traps baited with rotting liver or a blend of synthetic chemicals such as swormlure-4 . In this work, we evaluated the olfactory physiology of the screwworm fly and compared it with the non-obligate ectoparasitic secondary screwworm flies, C. macellaria, that invade necrotic wound and feed on dead tissue. These two species occur in geographically overlapping regions. C. macellaria , along with other blowflies such as the exotic C. megacephala , greatly outnumber C. hominivorax in the existing monitoring traps. Olfactory responses to swormlure-4 constituents between sex and mating status (mated vs unmated) in both species were recorded and compared. Overall, responses measured by the antennograms offered insights into the comparative olfactory physiology of the two fly species. We also present detailed analyses of the antennal transcriptome by RNA-Sequencing that reveal significant differences between male and female screwworm flies. The differential expression patterns were confirmed by quantitative PCR. Taken together, this integrated study provides insights into the physiological and molecular correlates of the screwworm’s attraction to wounds, and identifies molecular targets that will aid in the development of odorant-based fly management strategies.}, number={1}, journal={SCIENTIFIC REPORTS}, author={Hickner, Paul V. and Mittapalli, Omprakash and Subramoniam, Anjana and Sagel, Agustin and Watson, Wes and Scott, Maxwell J. and Arp, Alex P. and Leon, Adalberto A. Perez and Syed, Zainulabeuddin}, year={2020} }
 @article{yan_williamson_scott_2020, title={Using Moderate Transgene Expression to Improve the Genetic Sexing System of the Australian Sheep Blow Fly Lucilia cuprina}, volume={11}, ISSN={["2075-4450"]}, DOI={10.3390/insects11110797}, abstractNote={The sterile insect technique (SIT) is a promising strategy to control the Australian sheep blow fly Lucilia cuprina, a major pest of sheep. We have previously developed a transgenic embryonic sexing system (TESS) for this pest to facilitate the potential SIT application. TESS carry two transgenes, a tetracycline transactivator (tTA) driver and a tTA-activated pro-apoptotic effector. TESS females die at the embryonic stage unless tetracycline is supplied in the diet. However, undesired female sterility was observed in some TESS strains without tetracycline due to expression of tTA in ovaries. Here we investigate if TESS that combine transgenes with relatively low/moderate expression/activity improves the fertility of TESS females. tTA driver lines were evaluated for tTA expression by quantitative real time PCR and/or by crossing with a tTA-activated RFPex effector line. Fertility and lethality tests showed that a TESS strain containing a driver line with moderate tTA expression and an effector line showing moderate pro-apoptotic activity could recover the fertility of parental females and eliminated all female offspring at the embryonic stage. Consequently, such a strain could be further evaluated for an SIT program for L. cuprina, and such a “moderate strategy” could be considered for the TESS development in other pest species.}, number={11}, journal={INSECTS}, author={Yan, Ying and Williamson, Megan E. and Scott, Maxwell J.}, year={2020}, month={Nov} }
 @article{concha_wallbank_hanly_fenner_livraghi_rivera_paulo_arias_vargas_sanjeev_et al._2019, title={Interplay between Developmental Flexibility and Determinism in the Evolution of Mimetic Heliconius Wing Patterns}, volume={29}, ISSN={["1879-0445"]}, DOI={10.1016/j.cub.2019.10.010}, abstractNote={To what extent can we predict how evolution occurs? Do genetic architectures and developmental processes canalize the evolution of similar outcomes in a predictable manner? Or do historical contingencies impose alternative pathways to answer the same challenge? Examples of Müllerian mimicry between distantly related butterfly species provide natural replicates of evolution, allowing us to test whether identical wing patterns followed parallel or novel trajectories. Here, we explore the role that the signaling ligand WntA plays in generating mimetic wing patterns in Heliconius butterflies, a group with extraordinary mimicry-related wing pattern diversity. The radiation is relatively young, and numerous cases of wing pattern mimicry have evolved within the last 2.5-4.5 Ma. WntA is an important target of natural selection and is one of four major effect loci that underlie much of the pattern variation in the group. We used CRISPR/Cas9 targeted mutagenesis to generate WntA-deficient wings in 12 species and a further 10 intraspecific variants, including three co-mimetic pairs. In all tested butterflies, WntA knockouts affect pattern broadly and cause a shift among every possible scale cell type. Interestingly, the co-mimics lacking WntA were very different, suggesting that the gene networks that pattern a wing have diverged considerably among different lineages. Thus, although natural selection channeled phenotypic convergence, divergent developmental contexts between the two major Heliconius lineages opened different developmental routes to evolve resemblance. Consequently, even under very deterministic evolutionary scenarios, our results underscore a surprising unpredictability in the developmental paths underlying convergence in a recent radiation.}, number={23}, journal={CURRENT BIOLOGY}, author={Concha, Carolina and Wallbank, Richard W. R. and Hanly, Joseph J. and Fenner, Jennifer and Livraghi, Luca and Rivera, Edgardo Santiago and Paulo, Daniel F. and Arias, Carlos and Vargas, Marta and Sanjeev, Manu and et al.}, year={2019}, month={Dec}, pages={3996-+} }
 @article{paulo_williamson_arp_li_sagel_skoda_sanchez-gallego_vasquez_quintero_leon_et al._2019, title={Specific Gene Disruption in the Major Livestock Pests Cochliomyia hominivorax and Lucilia cuprina Using CRISPR/Cas9}, volume={9}, ISSN={["2160-1836"]}, DOI={10.1534/g3.119.400544}, abstractNote={Abstract Cochliomyia hominivorax and Lucilia cuprina are major pests of livestock. Their larvae infest warm-blooded vertebrates and feed on host’s tissues, resulting in severe industry losses. As they are serious pests, considerable effort has been made to develop genomic resources and functional tools aiming to improve their management and control. Here, we report a significant addition to the pool of genome manipulation tools through the establishment of efficient CRISPR/Cas9 protocols for the generation of directed and inheritable modifications in the genome of these flies. Site-directed mutations were introduced in the C. hominivorax and L. cuprina yellow genes (ChY and LcY) producing lightly pigmented adults. High rates of somatic mosaicism were induced when embryos were injected with Cas9 ribonucleoprotein complexes (RNPs) pre-assembled with guide RNAs (sgRNAs) at high concentrations. Adult flies carrying disrupted yellow alleles lacked normal pigmentation (brown body phenotype) and efficiently transmitted the mutated alleles to the subsequent generation, allowing the rapid creation of homozygous strains for reverse genetics of candidate loci. We next used our established CRISPR protocol to disrupt the C. hominivorax transformer gene (Chtra). Surviving females carrying mutations in the Chtra locus developed mosaic phenotypes of transformed ovipositors with characteristics of male genitalia while exhibiting abnormal reproductive tissues. The CRISPR protocol described here is a significant improvement on the existing toolkit of molecular methods in calliphorids. Our results also suggest that Cas9-based systems targeting Chtra and Lctra could be an effective means for controlling natural populations of these important pests.}, number={9}, journal={G3-GENES GENOMES GENETICS}, author={Paulo, Daniel F. and Williamson, Megan E. and Arp, Alex P. and Li, Fang and Sagel, Agustin and Skoda, Steven R. and Sanchez-Gallego, Joel and Vasquez, Mario and Quintero, Gladys and Leon, Adalberto A. and et al.}, year={2019}, month={Sep}, pages={3045–3055} }
 @article{davis_belikoff_scott_2018, title={Towards next generation maggot debridement therapy: Transgenic Lucilia sericata larvae that produce and secrete a human growth factor}, volume={26}, number={1}, journal={Wound Repair and Regeneration}, author={Davis, R. J. and Belikoff, E. J. and Scott, M. J.}, year={2018}, pages={A27–27} }
 @article{davis_belikoff_scholl_li_scott_2018, title={no blokes Is Essential for Male Viability and X Chromosome Gene Expression in the Australian Sheep Blowfly}, volume={28}, ISSN={["1879-0445"]}, DOI={10.1016/j.cub.2018.05.005}, abstractNote={It has been hypothesized that the Drosophila 4th chromosome is derived from an ancient X chromosome [1]. In the Australian sheep blowfly, Lucilia cuprina, the heterochromatic X chromosome contains few active genes and orthologs of Drosophila X-linked genes are autosomal. Of 8 X-linked genes identified previously in L. cuprina, 6 were orthologs of Drosophila 4th-chromosome genes [2]. The X-linked genes were expressed equally in males and females. Here we identify an additional 51 X-linked genes and show that most are dosage compensated. Orthologs of 49 of the 59 X-linked genes are on the 4th chromosome in D. melanogaster. Because painting of fourth (Pof) is important for expression of Drosophila 4th-chromosome genes [3], we used Cas9 to make a loss-of-function knockin mutation in an L. cuprina Pof ortholog we call no blokes (nbl). Homozygous nbl males derived from homozygous nbl mothers die at the late pupal stage. Homozygous nbl females are viable, fertile, and live longer than heterozygous nbl females. RNA expression of most X-linked genes was reduced in homozygous nbl male pupae and to a lesser extent in nbl females compared to heterozygous siblings. The results suggest that NBL could be important for X chromosome dosage compensation in L. cuprina. NBL may also facilitate gene expression in the heterochromatic environment of the X chromosome in both sexes. This study supports the hypothesis on the origin of the Drosophila 4th chromosome and that a POF-like protein was required for normal gene expression on the ancient X chromosome.}, number={12}, journal={CURRENT BIOLOGY}, author={Davis, Rebecca J. and Belikoff, Esther J. and Scholl, Elizabeth H. and Li, Fang and Scott, Maxwell J.}, year={2018}, month={Jun}, pages={1987-+} }
 @article{scott_gould_lorenzen_grubbs_edwards_o’brochta_2017, title={Agricultural production: assessment of the potential use of Cas9-mediated gene drive systems for agricultural pest control}, volume={5}, ISSN={2329-9460 2329-9037}, url={http://dx.doi.org/10.1080/23299460.2017.1410343}, DOI={10.1080/23299460.2017.1410343}, abstractNote={To highlight how gene drives could be useful for control of agricultural insect pests, we selected species that are pests of animals (New World screwworm), plants (spotted wing Drosophila, diamondback moth, Bemisia tabaci whitefly), or stored grains (red flour beetle). With the exception of whitefly, routine methods for delivering DNA to the germline and selecting for genetically modified insects have been developed. The traditional approach in agriculture has been to suppress insect pest populations using insecticides and other farming practices. Similarly, we suggest the main use of gene drives in agriculture will be for population suppression through targeting essential genes. We provide examples of gene drives that target specific genes including female-essential genes. Further, we discuss issues related to containment in the laboratory and eventual field testing of strains harboring a Cas9-mediated gene drive system.}, number={sup1}, journal={Journal of Responsible Innovation}, publisher={Informa UK Limited}, author={Scott, Maxwell J. and Gould, Fred and Lorenzen, Marcé and Grubbs, Nathaniel and Edwards, Owain and O’Brochta, David}, year={2017}, month={Dec}, pages={S98–S120} }
 @article{yan_linger_scott_2017, title={Building early-larval sexing systems for genetic control of the Australian sheep blow fly Lucilia cuprina using two constitutive promoters}, volume={7}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-017-02763-4}, abstractNote={Abstract Transgenic sexing strains (TSS) that carry conditional female lethal genes are advantageous for genetic control programs based on the sterile insect technique (SIT). It is desirable if females die early in development as larval diet is a major cost for mass production facilities. This can be achieved by using a gene promoter that is only active in embryos to drive expression of the tetracycline transactivator (tTA), the transcription factor commonly used in two-component TSS. While an embryo-specific promoter is ideal it may not be essential for assembling an effective TSS as tTA can be repressed by addition of tetracycline to the diet at larval and/or adult stages. Here we have investigated this idea by isolating and employing the promoters from the Lucilia spitting image and actin 5C genes to drive tTA expression in embryos and later stages. L. cuprina TSS with the tTA drivers and tTA-regulated tetO-Lshid effectors produced only females when raised on a limited tetracycline diet. The Lshid transgene contains a sex-specific intron and as a consequence only females produce LsHID protein. TSS females died at early larval stages, which makes the lines advantageous for an SIT program.}, journal={SCIENTIFIC REPORTS}, author={Yan, Ying and Linger, Rebecca J. and Scott, Maxwell J.}, year={2017}, month={May} }
 @article{scott_concha_welch_phillips_skoda_2017, title={Review of research advances in the screwworm eradication program over the past 25 years}, volume={164}, ISSN={["1570-7458"]}, DOI={10.1111/eea.12607}, abstractNote={New World screwworms, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae: Chrysomyinae), are devastating pests of warm-blooded animals that cause significant economic damage to livestock. The successful campaign to eradicate screwworms from continental North America, led by the US Department of Agriculture and using the sterile insect technique, continues to receive research support that has resulted in improved technologies for all aspects of the program. The process and ingredients for mass-rearing screwworms is more efficient and sustainable, and there is now a standardized protocol for developing new strains used in mass rearing. Cryopreservation of screwworm embryos allows strains to be preserved and recovered if necessary and also reduces rearing requirements for backup and research strains. Sterile fly release procedures and equipment have been updated leading to optimized sterile fly release rates. Surveillance for screwworm infestations and outbreaks have incorporated new trap designs, habitat analysis, and molecular genetic techniques that enhance monitoring the progress of the program as well as early detection and response to outbreaks. Genetic analyses of screwworm populations across their current range have increased the understanding of genetic differentiation, which may aide in developing new strains and determining the geographic origin of screwworms causing outbreaks when they occur. The ability to release only sterile males, which has been a goal of the program for over 60 years, has recently been accomplished through the development of transgenic sexing strains. The strains carry a conditional female lethal gene and are comparable to the wild-type strain for several biological parameters that are important for mass production and performance in the field. The strains should improve efficiency of population suppression of the current and future eradication and prevention programs against screwworms. These research advances as well as future considerations are presented.}, number={3}, journal={ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA}, author={Scott, Maxwell J. and Concha, Carolina and Welch, John B. and Phillips, Pamela L. and Skoda, Steven R.}, year={2017}, month={Sep}, pages={226–236} }
 @article{dearden_gemmell_mercier_lester_scott_newcomb_buckley_jacobs_goldson_penman_2017, title={The potential for the use of gene drives for pest control in New Zealand: a perspective}, volume={48}, ISSN={0303-6758 1175-8899}, url={http://dx.doi.org/10.1080/03036758.2017.1385030}, DOI={10.1080/03036758.2017.1385030}, abstractNote={Genetic technologies such as gene editing and gene drive systems have recently emerged as potential tools for pest control. Gene drives, in particular, have been described as potential solutions to the pest problems that beset New Zealand. Here we describe the current state of gene drive technologies and present a series of examples to examine the potential benefits and problems arising from gene drive approaches for pest control in New Zealand. We consider the risks and barriers, both biological and social, that would need to be addressed to deploy such systems against our key pests with particular reference to the unique characteristics of New Zealand’s biota, environment and peoples. Gene drives are a potentially useful technology for the eradication of pests in New Zealand but a great deal of research and understanding, as well as public acceptance, is required before they can be implemented.}, number={4}, journal={Journal of the Royal Society of New Zealand}, publisher={Informa UK Limited}, author={Dearden, Peter K. and Gemmell, Neil J. and Mercier, Ocean R. and Lester, Philip J. and Scott, Maxwell J. and Newcomb, Richard D. and Buckley, Thomas R. and Jacobs, Jeanne M. E. and Goldson, Stephen G. and Penman, David R.}, year={2017}, month={Oct}, pages={225–244} }
 @misc{anstead_batterham_korhonen_young_hall_bowles_richards_scott_gasser_2016, title={A blow to the fly - Lucilia cuprina draft genome and transcriptome to support advances in biology and biotechnology}, volume={34}, ISSN={["1873-1899"]}, DOI={10.1016/j.biotechadv.2016.02.009}, abstractNote={The blow fly, Lucilia cuprina (Wiedemann, 1830) is a parasitic insect of major global economic importance. Maggots of this fly parasitize the skin of animal hosts, feed on excretions and tissues, and cause severe disease (flystrike or myiasis). Although there has been considerable research on L. cuprina over the years, little is understood about the molecular biology, biochemistry and genetics of this parasitic fly, as well as its relationship with its hosts and the disease that it causes. This situation might change with the recent report of the draft genome and transcriptome of this blow fly, which has given new and global insights into its biology, interactions with the host animal and aspects of insecticide resistance at the molecular level. This genomic resource will likely enable many fundamental and applied research areas in the future. The present article gives a background on L. cuprina and myiasis, a brief account of past and current treatment, prevention and control approaches, and provides a perspective on the impact that the L. cuprina genome should have on future research of this and related parasitic flies, and the design of new and improved interventions for myiasis.}, number={5}, journal={BIOTECHNOLOGY ADVANCES}, author={Anstead, Clare A. and Batterham, Philip and Korhonen, Pasi K. and Young, Neil D. and Hall, Ross S. and Bowles, Vernon M. and Richards, Stephen and Scott, Maxwell J. and Gasser, Robin B.}, year={2016}, pages={605–620} }
 @article{concha_palavesam_guerrero_sagel_li_osborne_hernandez_pardo_quintero_vasquez_et al._2016, title={A transgenic male-only strain of the New World screwworm for an improved control program using the sterile insect technique}, volume={14}, journal={BMC Biology}, author={Concha, C. and Palavesam, A. and Guerrero, F. D. and Sagel, A. and Li, F. and Osborne, J. A. and Hernandez, Y. and Pardo, T. and Quintero, G. and Vasquez, M. and et al.}, year={2016} }
 @article{li_scott_2016, title={CRISPR/Cas9-mediated mutagenesis of the white and Sex lethal loci in the invasive pest, Drosophila suzukii}, volume={469}, ISSN={["1090-2104"]}, DOI={10.1016/j.bbrc.2015.12.081}, abstractNote={Drosophila suzukii (commonly called spotted wing Drosophila) is an invasive pest of soft-skinned fruit (e.g. blueberries, strawberries). A high quality reference genome sequence is available but functional genomic tools, such as used in Drosophila melanogaster, remain to be developed. In this study we have used the CRISPR/Cas9 system to introduce site-specific mutations in the D. suzukii white (w) and Sex lethal (Sxl) genes. Hemizygous males with w mutations develop white eyes and the mutant genes are transmissible to the next generation. Somatic mosaic females that carry mutations in the Sxl gene develop abnormal genitalia and reproductive tissue. The D. suzukii Sxl gene could be an excellent target for a Cas9-mediated gene drive to suppress populations of this highly destructive pest.}, number={4}, journal={BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS}, author={Li, Fang and Scott, Maxwell J.}, year={2016}, month={Jan}, pages={911–916} }
 @article{scott_benedict_2016, title={Concept and history of genetic control}, journal={Genetic Control of Malaria and Dengue}, author={Scott, M. J. and Benedict, M. Q.}, year={2016}, pages={31–54} }
 @article{schwartz_truglio_scott_fitzsimons_2016, title={Long-Term Memory in Drosophila Is Influenced by Histone Deacetylase HDAC4 Interacting with SUMO-Conjugating Enzyme Ubc9}, volume={203}, ISSN={["1943-2631"]}, DOI={10.1534/genetics.115.183194}, abstractNote={Abstract HDAC4 is a potent memory repressor with overexpression of wild type or a nuclear-restricted mutant resulting in memory deficits. Interestingly, reduction of HDAC4 also impairs memory via an as yet unknown mechanism. Although histone deacetylase family members are important mediators of epigenetic mechanisms in neurons, HDAC4 is predominantly cytoplasmic in the brain and there is increasing evidence for interactions with nonhistone proteins, suggesting HDAC4 has roles beyond transcriptional regulation. To that end, we performed a genetic interaction screen in Drosophila and identified 26 genes that interacted with HDAC4, including Ubc9, the sole SUMO E2-conjugating enzyme. RNA interference-induced reduction of Ubc9 in the adult brain impaired long-term memory in the courtship suppression assay, a Drosophila model of associative memory. We also demonstrate that HDAC4 and Ubc9 interact genetically during memory formation, opening new avenues for investigating the mechanisms through which HDAC4 regulates memory formation and other neurological processes.}, number={3}, journal={GENETICS}, author={Schwartz, Silvia and Truglio, Mauro and Scott, Maxwell J. and Fitzsimons, Helen L.}, year={2016}, month={Jul}, pages={1249-+} }
 @article{linger_belikoff_yan_li_wantuch_fitzsimons_scott_2016, title={Towards next generation maggot debridement therapy: transgenic Lucilia sericata larvae that produce and secrete a human growth factor}, volume={16}, ISSN={["1472-6750"]}, DOI={10.1186/s12896-016-0263-z}, abstractNote={Diabetes and its concurrent complications impact a significant proportion of the population of the US and create a large financial burden on the American health care system. FDA-approved maggot debridement therapy (MDT), the application of sterile laboratory-reared Lucilia sericata (green bottle fly) larvae to wounds, is a cost-effective and successful treatment for diabetic foot ulcers and other medical conditions. Human platelet derived growth factor-BB (PDGF-BB) is a secreted dimeric peptide growth factor that binds the PDGF receptor. PDGF-BB stimulates cell proliferation and survival, promotes wound healing, and has been investigated as a possible topical treatment for non-healing wounds. Genetic engineering has allowed for expression and secretion of human growth factors and other proteins in transgenic insects. Here, we present a novel concept in MDT technology that combines the established benefits of MDT with the power of genetic engineering to promote healing. The focus of this study is to create and characterize strains of transgenic L. sericata that express and secrete PDGF-BB at detectable levels in adult hemolymph, whole larval lysate, and maggot excretions/ secretions (ES), with potential for clinical utility in wound healing.We have engineered and confirmed transgene insertion in several strains of L. sericata that express human PDGF-BB. Using a heat-inducible promoter to control the pdgf-b gene, pdgf-b mRNA was detected via semi-quantitative PCR upon heat shock. PDGF-BB protein was also detectable in larval lysates and adult hemolymph but not larval ES. An alternative, tetracycline-repressible pdgf-b system mediated expression of pdgf-b mRNA when maggots were raised on diet that lacked tetracycline. Further, PDGF-BB protein was readily detected in whole larval lysate as well as larval ES.Here we show robust, inducible expression and production of human PDGF-BB protein from two conditional expression systems in transgenic L. sericata larvae. The tetracycline-repressible system appears to be the most promising as PDGF-BB protein was detectable in larval ES following induction. Our system could potentially be used to deliver a variety of growth factors and anti-microbial peptides to the wound environment with the aim of enhancing wound healing, thereby improving patient outcome in a cost-effective manner.}, journal={BMC BIOTECHNOLOGY}, author={Linger, Rebecca J. and Belikoff, Esther J. and Yan, Ying and Li, Fang and Wantuch, Holly A. and Fitzsimons, Helen L. and Scott, Maxwell J.}, year={2016}, month={Mar} }
 @article{yan_scott_2015, title={A transgenic embryonic sexing system for the Australian sheep blow fly Lucilia cuprina}, volume={5}, ISSN={["2045-2322"]}, DOI={10.1038/srep16090}, abstractNote={Genetic approaches, including the sterile insect technique (SIT), have previously been considered for control of the Australian sheep blow fly Lucilia cuprina, a major pest of sheep. In an SIT program, females consume 50% of the diet but are ineffective as control agents and compete with females in the field for mating with sterile males, thereby decreasing the efficiency of the program. Consequently, transgenic sexing strains of L. cuprina were developed that produce 100% males when raised on diet that lacks tetracycline. However, as females die mostly at the pupal stage, rearing costs would not be significantly reduced. Here we report the development of transgenic embryonic sexing strains of L. cuprina. In these strains, the Lsbnk cellularization gene promoter drives high levels of expression of the tetracycline transactivator (tTA) in the early embryo. In the absence of tetracycline, tTA activates expression of the Lshid proapoptotic gene, leading to death of the embryo. Sex-specific RNA splicing of Lshid transcripts ensures that only female embryos die. Embryonic sexing strains were also made by combining the Lsbnk-tTA and tetO-Lshid components into a single gene construct, which will facilitate transfer of the technology to other major calliphorid livestock pests.}, journal={SCIENTIFIC REPORTS}, author={Yan, Ying and Scott, Maxwell J.}, year={2015}, month={Nov} }
 @article{linger_belikoff_scott_2015, title={Dosage Compensation of X-Linked Muller Element F Genes but Not X-Linked Transgenes in the Australian Sheep Blowfly}, volume={10}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0141544}, abstractNote={In most animals that have X and Y sex chromosomes, chromosome-wide mechanisms are used to balance X-linked gene expression in males and females. In the fly Drosophila melanogaster, the dosage compensation mechanism also generally extends to X-linked transgenes. Over 70 transgenic lines of the Australian sheep blowfly Lucilia cuprina have been made as part of an effort to develop male-only strains for a genetic control program of this major pest of sheep. All lines carry a constitutively expressed fluorescent protein marker gene. In all 12 X-linked lines, female larvae show brighter fluorescence than male larvae, suggesting the marker gene is not dosage compensated. This has been confirmed by quantitative RT-PCR for selected lines. To determine if endogenous X-linked genes are dosage compensated, we isolated 8 genes that are orthologs of genes that are on the fourth chromosome in D. melanogaster. Recent evidence suggests that the D. melanogaster fourth chromosome, or Muller element F, is the ancestral X chromosome in Diptera that has reverted to an autosome in Drosophila species. We show by quantitative PCR of male and female DNA that 6 of the 8 linkage group F genes reside on the X chromosome in L. cuprina. The other two Muller element F genes were found to be autosomal in L. cuprina, whereas two Muller element B genes were found on the same region of the X chromosome as the L. cuprina orthologs of the D. melanogaster Ephrin and gawky genes. We find that the L. cuprina X chromosome genes are equally expressed in males and females (i.e., fully dosage compensated). Thus, unlike in Drosophila, it appears that the Lucilia dosage compensation system is specific for genes endogenous to the X chromosome and cannot be co-opted by recently arrived transgenes.}, number={10}, journal={PLOS ONE}, author={Linger, Rebecca J. and Belikoff, Esther J. and Scott, Maxwell J.}, year={2015}, month={Oct} }
 @article{edman_linger_belikoff_li_sze_tarone_scott_2015, title={Functional characterization of calliphorid cell death genes and cellularization gene promoters for controlling gene expression and cell viability in early embryos}, volume={24}, ISSN={["1365-2583"]}, DOI={10.1111/imb.12135}, abstractNote={The New World screwworm fly, Cochliomyia hominivorax, and the Australian sheep blow fly, Lucilia cuprina, are major pests of livestock. The sterile insect technique was used to eradicate C. hominivorax from North and Central America. This involved area-wide releases of male and female flies that had been sterilized by radiation. Genetic systems have been developed for making ‘male-only’ strains that would improve the efficiency of genetic control of insect pests. One system involves induction of female lethality in embryos through activation of a pro-apoptotic gene by the tetracycline-dependent transactivator. Sex-specific expression is achieved using an intron from the transformer gene, which we previously isolated from several calliphorids. In the present study, we report the isolation of the promoters from the C. hominivorax slam and Lucilia sericata bnk cellularization genes and show that these promoters can drive expression of a GFP reporter gene in early embryos of transgenic L. cuprina. Additionally, we report the isolation of the L. sericata pro-apoptotic hid and rpr genes, identify conserved motifs in the encoded proteins and determine the relative expression of these genes at different stages of development. We show that widespread expression of the L. sericata pro-apoptotic genes was lethal in Drosophila melanogaster. The isolated gene promoters and pro-apoptotic genes could potentially be used to build transgenic embryonic sexing strains of calliphorid livestock pests.}, number={1}, journal={INSECT MOLECULAR BIOLOGY}, author={Edman, R. M. and Linger, R. J. and Belikoff, E. J. and Li, F. and Sze, S. -H. and Tarone, A. M. and Scott, M. J.}, year={2015}, month={Feb}, pages={58–70} }
 @misc{sandeman_levot_heath_james_greeff_scott_batterham_bowles_2014, title={Control of the sheep blowfly in Australia and New Zealand - are we there yet?}, volume={44}, ISSN={["1879-0135"]}, DOI={10.1016/j.ijpara.2014.08.009}, abstractNote={The last 50 years of research into infections in Australia and New Zealand caused by larvae of the sheep blowfly, Lucilia cuprina, have significantly advanced our understanding of this blowfly and its primary host, the sheep. However, apart from some highly effective drugs it could be argued that no new control methodologies have resulted. This review addresses the major areas of sheep blowfly research over this period describing the significant outcomes and analyses, and what is still required to produce new commercial control technologies. The use of drugs against this fly species has been very successful but resistance has developed to almost all current compounds. Integrated pest management is becoming basic to control, especially in the absence of mulesing, and has clearly benefited from computer-aided technologies. Biological control has more challenges but natural and perhaps transformed biopesticides offer possibilities for the future. Experimental vaccines have been developed but require further analysis of antigens and formulations to boost protection. Genetic technologies may provide potential for long-term control through more rapid indirect selection of sheep less prone to flystrike. Finally in the future, genetic analysis of the fly may allow suppression and perhaps eradication of blowfly populations or identification of new and more viable targets for drug and vaccine intervention. Clearly all these areas of research offer potential new controls but commercial development is perhaps inhibited by the success of current chemical insecticides and certainly requires a significant additional injection of resources.}, number={12}, journal={INTERNATIONAL JOURNAL FOR PARASITOLOGY}, author={Sandeman, R. M. and Levot, G. W. and Heath, A. C. G. and James, P. J. and Greeff, J. C. and Scott, M. J. and Batterham, P. and Bowles, V. M.}, year={2014}, month={Oct}, pages={879–891} }
 @article{scott_2014, title={Development and evaluation of male-only strains of the Australian sheep blowfly, Lucilia cuprina}, volume={15}, ISSN={["1471-2156"]}, DOI={10.1186/1471-2156-15-s2-s3}, abstractNote={Abstract The Australian sheep blowfly Lucilia cuprina (Wiedemann) is a major pest of sheep in Australia and New Zealand. From the 1960s to the 1980s there was a major effort to develop "field female killing" or FFK strains of L. cuprina that could be used for a cost-effective genetic control program. The FFK strains carried eye color mutations that were lethal to females in the field but not under conditions in the mass rearing facility. Males did not die in the field as normal copies of the eye color genes had been translocated to the Y chromosome and an autosome. Although the FFK strains showed some promise in field tests, a genetic control program in mainland Australia was never implemented for several reasons including instability of the FFK strains during mass rearing. A stable transgenic strain of L. cuprina that carried one or more dominant repressible female lethal genes offered the potential for efficient genetic control of blowfly populations. Here I review our research on tetracycline-repressible female lethal genetic systems, Lucilia germ-line transformation and sex determination genes that ultimately led to the successful development of transgenic "male-only" strains of L. cuprina . The technology developed for L. cuprina should be directly transferable to other blowfly livestock pests including L. sericata and the New World and Old World screwworm. 29}, journal={BMC GENETICS}, author={Scott, Maxwell J.}, year={2014}, month={Dec} }
 @article{watanabe_hattori_berriman_lehane_hall_solano_aksoy_hide_toure_attardo_et al._2014, title={Genome sequence of the tsetse fly (Glossina morsitans): vector of African trypanosomiasis}, volume={344}, number={6182}, journal={Science}, author={Watanabe, J. and Hattori, M. and Berriman, M. and Lehane, M. J. and Hall, N. and Solano, P. and Aksoy, S. and Hide, W. and Toure, Y. and Attardo, G. M. and et al.}, year={2014}, pages={380–386} }
 @article{scott_pimsler_tarone_2014, title={Sex Determination Mechanisms in the Calliphoridae (Blow Flies)}, volume={8}, ISSN={["1661-5433"]}, DOI={10.1159/000357132}, abstractNote={The Calliphoridae or blow flies are a family of insects that occupy diverse habitats and perform important ecological roles, particularly the decomposition of animal remains. Some Calliphoridae species are also important in the forensic sciences, in agriculture (e.g. as livestock pests) and in medicine (e.g. maggot therapy). Calliphoridae provide striking examples in support of the hypothesis that sex determination regulatory gene hierarchies evolve in the reverse order, with the gene at the top being the most recently added. Unlike the model fly <i>Drosophila melanogaster</i>, where sex is determined by the number of X chromosomes, in the Australian sheep blow fly <i>(Lucilia cuprina)</i> sex is determined by a Y-linked male-determining gene <i>(M)</i>. A different regulatory system appears to operate in the hairy maggot blow fly <i>(Chrysomya rufifacies)</i> where the maternal genotype determines sex. It is hypothesized that females heterozygous for a dominant female-determining factor <i>(F/f)</i> produce only female offspring and homozygous<i> f/f</i> females produce only sons. The bottom of the regulatory hierarchy appears to be the same in <i>D. melanogaster</i> and <i>L. cuprina</i>, with sex-specific splicing of <i>doublesex</i> transcripts being controlled by the female-specific Transformer (TRA) protein. We discuss a model that has been proposed for how <i>tra</i> transcripts are sex-specifically spliced in calliphorids, which is very different from <i>D. melanogaster.</i>}, number={1-3}, journal={SEXUAL DEVELOPMENT}, author={Scott, M. J. and Pimsler, M. L. and Tarone, A. M.}, year={2014}, pages={29–37} }
 @article{scott_morrison_simmons_2014, title={Transgenic approaches for sterile insect control of dipteran livestock pests and lepidopteran crop pests}, journal={Transgenic insects: techniques and applications}, author={Scott, M. J. and Morrison, N. I. and Simmons, G. S.}, year={2014}, pages={152–167} }
 @article{li_wantuch_linger_belikoff_scott_2014, title={Transgenic sexing system for genetic control of the Australian sheep blow fly Lucilia cuprina}, volume={51}, ISSN={["1879-0240"]}, DOI={10.1016/j.ibmb.2014.06.001}, abstractNote={The New World screwworm and the Australian sheep blowfly Lucilia cuprina are devastating pests of livestock. The larvae of these species feed on the tissue of the living animal and can cause death if untreated. The sterile insect technique or SIT was used to eradicate screwworm from North and Central America. This inspired efforts to develop strains containing complex chromosomal rearrangements for genetic control of L. cuprina in Australia. Although one field trial was promising, the approach was abandoned due to costs and difficulties in mass rearing the strain. As the efficiency of SIT can be significantly increased if only sterile males are released, we have developed transgenic strains of L. cuprina that carry a dominant tetracycline repressible female lethal genetic system. Lethality is due to overexpression of an auto-regulated tetracycline repressible transactivator (tTA) gene and occurs mostly at the pupal stage. Dominant female lethality was achieved by replacing the Drosophila hsp70 core promoter with a Lucilia hsp70 core promoter-5′UTR for tTA overexpression. The strains carry a dominant strongly expressed marker that will facilitate identification in the field. Interestingly, the sexes could be reliably sorted by fluorescence or color from the early first instar larval stage as females that overexpress tTA also overexpress the linked marker gene. Male-only strains of L. cuprina developed in this study could form the basis for a future genetic control program. Moreover, the system developed for L. cuprina should be readily transferrable to other major calliphorid livestock pests including the New and Old World screwworm.}, journal={INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY}, author={Li, Fang and Wantuch, Holly A. and Linger, Rebecca J. and Belikoff, Esther J. and Scott, Maxwell J.}, year={2014}, month={Aug}, pages={80–88} }
 @article{li_vensko_belikoff_scott_2013, title={Conservation and Sex-Specific Splicing of the transformer Gene in the Calliphorids Cochliomyia hominivorax, Cochliomyia macellaria and Lucilia sericata}, volume={8}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0056303}, abstractNote={Transformer (TRA) promotes female development in several dipteran species including the Australian sheep blowfly Lucilia cuprina, the Mediterranean fruit fly, housefly and Drosophila melanogaster. tra transcripts are sex-specifically spliced such that only the female form encodes full length functional protein. The presence of six predicted TRA/TRA2 binding sites in the sex-specific female intron of the L. cuprina gene suggested that tra splicing is auto-regulated as in medfly and housefly. With the aim of identifying conserved motifs that may play a role in tra sex-specific splicing, here we have isolated and characterized the tra gene from three additional blowfly species, L. sericata, Cochliomyia hominivorax and C. macellaria. The blowfly adult male and female transcripts differ in the choice of splice donor site in the first intron, with males using a site downstream of the site used in females. The tra genes all contain a single TRA/TRA2 site in the male exon and a cluster of four to five sites in the male intron. However, overall the sex-specific intron sequences are poorly conserved in closely related blowflies. The most conserved regions are around the exon/intron junctions, the 3' end of the intron and near the cluster of TRA/TRA2 sites. We propose a model for sex specific regulation of tra splicing that incorporates the conserved features identified in this study. In L. sericata embryos, the male tra transcript was first detected at around the time of cellular blastoderm formation. RNAi experiments showed that tra is required for female development in L. sericata and C. macellaria. The isolation of the tra gene from the New World screwworm fly C. hominivorax, a major livestock pest, will facilitate the development of a "male-only" strain for genetic control programs.}, number={2}, journal={PLOS ONE}, author={Li, Fang and Vensko, Steven P., II and Belikoff, Esther J. and Scott, Maxwell J.}, year={2013}, month={Feb} }
 @article{fitzsimons_schwartz_given_scott_2013, title={The Histone Deacetylase HDAC4 Regulates Long-Term Memory in Drosophila}, volume={8}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0083903}, abstractNote={A growing body of research indicates that pharmacological inhibition of histone deacetylases (HDACs) correlates with enhancement of long-term memory and current research is concentrated on determining the roles that individual HDACs play in cognitive function. Here, we investigate the role of HDAC4 in long-term memory formation in Drosophila. We show that overexpression of HDAC4 in the adult mushroom body, an important structure for memory formation, resulted in a specific impairment in long-term courtship memory, but had no affect on short-term memory. Overexpression of an HDAC4 catalytic mutant also abolished LTM, suggesting a mode of action independent of catalytic activity. We found that overexpression of HDAC4 resulted in a redistribution of the transcription factor MEF2 from a relatively uniform distribution through the nucleus into punctate nuclear bodies, where it colocalized with HDAC4. As MEF2 has also been implicated in regulation of long-term memory, these data suggest that the repressive effects of HDAC4 on long-term memory may be through interaction with MEF2. In the same genetic background, we also found that RNAi-mediated knockdown of HDAC4 impairs long-term memory, therefore we demonstrate that HDAC4 is not only a repressor of long-term memory, but also modulates normal memory formation.}, number={12}, journal={PLOS ONE}, author={Fitzsimons, Helen L. and Schwartz, Silvia and Given, Fiona M. and Scott, Maxwell J.}, year={2013}, month={Dec} }
 @article{sze_dunham_carey_chang_li_edman_fjeldsted_scott_nuzhdin_tarone_2012, title={A de novo transcriptome assembly of Lucilia sericata (Diptera: Calliphoridae) with predicted alternative splices, single nucleotide polymorphisms and transcript expression estimates}, volume={21}, ISSN={["1365-2583"]}, DOI={10.1111/j.1365-2583.2011.01127.x}, abstractNote={The blow fly Lucilia sericata (Diptera: Calliphoridae) (Meigen) is a nonmodel organism with no reference genome that is associated with numerous areas of research spanning the ecological, evolutionary, medical, veterinary and forensic sciences. To facilitate scientific discovery in this species, the transcriptome was assembled from more than six billion bases of Illumina and twenty-one million bases of 454 sequence derived from embryonic, larval, pupal, adult and larval salivary gland libraries. The assembly was carried out in a manner that enabled identification of putative single nucleotide polymorphisms (SNPs) and alternative splices, and that provided expression estimates for various life history stages and for salivary tissue. The assembled transcriptome was also used to identify transcribed transposable elements in L. sericata. The results of this study will enable blow fly biologists, dipterists and comparative genomicists to more rapidly develop and test molecular and genetic hypotheses, especially those regarding blow fly development and salivary gland biology.}, number={2}, journal={INSECT MOLECULAR BIOLOGY}, author={Sze, S-H. and Dunham, J. P. and Carey, B. and Chang, P. L. and Li, F. and Edman, R. M. and Fjeldsted, C. and Scott, M. J. and Nuzhdin, S. V. and Tarone, A. M.}, year={2012}, month={Apr}, pages={205–221} }
 @article{stasiuk_scott_grant_2012, title={Developmental plasticity and the evolution of parasitism in an unusual nematode, Parastrongyloides trichosuri}, volume={3}, ISSN={["2041-9139"]}, DOI={10.1186/2041-9139-3-1}, abstractNote={Abstract Background Parasitism is an important life history strategy in many metazoan taxa. This is particularly true of the Phylum Nematoda, in which parasitism has evolved independently at least nine times. The apparent ease with which parasitism has evolved amongst nematodes may, in part, be due to a feature of nematode development acting as a pre-adaptation for the transition from a free-living to a parasitic life history. One candidate pre-adaptive feature for evolution in terrestrial nematodes is the dauer larva, a developmentally arrested morph formed in response to environmental signals. Results We investigated the role of dauer development in the nematode, Parastrongyloides trichosuri , which has retained a complete free-living life cycle in addition to a life cycle as a mammalian gastrointestinal parasite. We show that the developmental switch between these life histories is sensitive to the same environmental cues as dauer arrest in free-living nematodes, including sensitivity to a chemical cue produced by the free-living stages. Furthermore, we show that genetic variation for the sensitivity of the cue(s) exists in natural populations of P. trichosuri , such that we derived inbred lines that were largely insensitive to the cue and other lines that were supersensitive to the cue. Conclusions For this parasitic clade, and perhaps more widely in the phylum, the evolution of parasitism co-opted the dauer switch of a free-living ancestor. This lends direct support to the hypothesis that the switch to developmental arrest in the dauer larva acted as a pre-adaptation for the evolution of parasitism, and suggests that the sensory transduction machinery downstream of the cue may have been similarly co-opted and modified.}, journal={EVODEVO}, author={Stasiuk, Susan J. and Scott, Maxwell J. and Grant, Warwick N.}, year={2012}, month={Jan} }
 @article{concha_edman_belikoff_schiemann_carey_scott_2012, title={Organization and expression of the Australian sheep blowfly (Lucilia cuprina) hsp23, hsp24, hsp70 and hsp83 genes}, volume={21}, ISSN={["0962-1075"]}, DOI={10.1111/j.1365-2583.2011.01123.x}, abstractNote={In this study we report the isolation and characterization of a heat shock protein 70 (hsp70) gene, the hsp83 gene and two genes that encode small Hsps (Lchsp23 and Lchsp24) from the Australian sheep blowfly, Lucilia cuprina, a major agricultural pest. Phylogenetic analyses indicate that the LcHsp23 protein is the orthologue of Drosophila melanogaster Hsp23 and LcHsp24 is the orthologue of Sarcophaga crassipalpis Hsp23. Quantitative reverse-transcriptase PCR analysis showed that the basal level of Lchsp83 RNA is relatively high at all developmental stages and only moderately induced by heat shock. In contrast, Lchsp70 transcripts are present at low levels and strongly induced by heat shock at all stages. The basal levels of expression and degrees of heat induction of the Lchsp23 and Lchsp24 transcripts were more variable across the different developmental stages. Putative heat shock factor binding sites were identified in the Lchsp24, Lchsp70 and Lchsp83 gene promoters. The isolation of these hsp gene promoters will facilitate constitutive or conditional expression of a gene of interest in transgenic Lucilia.}, number={2}, journal={INSECT MOLECULAR BIOLOGY}, author={Concha, C. and Edman, R. M. and Belikoff, E. J. and Schiemann, A. H. and Carey, B. and Scott, M. J.}, year={2012}, month={Apr}, pages={169–180} }
 @article{concha_belikoff_carey_li_schiemann_scott_2011, title={Efficient germ-line transformation of the economically important pest species Lucilia cuprina and Lucilia sericata (Diptera, Calliphoridae)}, volume={41}, ISSN={["1879-0240"]}, DOI={10.1016/j.ibmb.2010.09.006}, abstractNote={The green blowfly species Lucilia cuprina and Lucilia sericata are economically important pests for the sheep industries of Australia and New Zealand. L. cuprina has long been considered a good target for a genetic pest management program. In addition, L. sericata maggots are used in the cleaning of wounds and necrotic tissue of patients suffering from ulcers that are difficult to treat by other methods. Development of efficient transgenesis methods would greatly facilitate the development of strains ideal for genetic control programs or could potentially improve “maggot therapy”. We have previously reported the germ-line transformation of L. cuprina and the design of a “female killing system” that could potentially be applied to this species. However, the efficiency of transformation obtained was low and transformed lines were difficult to detect due to the low expression of the EGFP marker used. Here we describe an efficient and reliable method for germ-line transformation of L. cuprina using new piggyBac vector and helper plasmids containing the strong promoter from the L. cuprina hsp83 gene to drive expression of the transposase and fluorescent protein marker gene. We also report, for the first time, the germ-line transformation of L. sericata using the new piggyBac vector/helper combination.}, number={1}, journal={INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY}, author={Concha, Carolina and Belikoff, Esther J. and Carey, Brandi-lee and Li, Fang and Schiemann, Anja H. and Scott, Maxwell J.}, year={2011}, month={Jan}, pages={70–75} }
 @article{fitzsimons_scott_2011, title={Genetic Modulation of Rpd3 Expression Impairs Long-Term Courtship Memory in Drosophila}, volume={6}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0029171}, abstractNote={There is increasing evidence that regulation of local chromatin structure is a critical mechanism underlying the consolidation of long-term memory (LTM), however considerably less is understood about the specific mechanisms by which these epigenetic effects are mediated. Furthermore, the importance of histone acetylation in Drosophila memory has not been reported. The histone deacetylase (HDAC) Rpd3 is abundant in the adult fly brain, suggesting a post-mitotic function. Here, we investigated the role of Rpd3 in long-term courtship memory in Drosophila. We found that while modulation of Rpd3 levels predominantly in the adult mushroom body had no observed impact on immediate recall or one-hour memory, 24-hour LTM was severely impaired. Surprisingly, both overexpression as well as RNAi-mediated knockdown of Rpd3 resulted in impairment of long-term courtship memory, suggesting that the dose of Rpd3 is critical for normal LTM.}, number={12}, journal={PLOS ONE}, author={Fitzsimons, Helen L. and Scott, Maxwell J.}, year={2011}, month={Dec} }
 @article{scott_atapattu_schiemann_concha_henry_carey_belikoff_heinrich_sarkar_2011, title={Organisation and expression of a cluster of yolk protein genes in the Australian sheep blowfly, Lucilia cuprina}, volume={139}, ISSN={["0016-6707"]}, DOI={10.1007/s10709-010-9492-6}, number={1}, journal={GENETICA}, author={Scott, Maxwell J. and Atapattu, Asela and Schiemann, Anja H. and Concha, Carolina and Henry, Rebecca and Carey, Brandi-lee and Belikoff, Esther J. and Heinrich, Joerg C. and Sarkar, Abhimanyu}, year={2011}, month={Jan}, pages={63–70} }
 @article{concha_li_scott_2010, title={Conservation and sex-specific splicing of the doublesex gene in the economically important pest species Lucilia cuprina}, volume={89}, ISSN={["0973-7731"]}, DOI={10.1007/s12041-010-0039-5}, number={3}, journal={JOURNAL OF GENETICS}, author={Concha, Carolina and Li, Fang and Scott, Maxwell J.}, year={2010}, month={Sep}, pages={279–285} }
 @article{schiemann_li_weake_belikoff_klemmer_moore_scott_2010, title={Sex-biased transcription enhancement by a 5 ' tethered Gal4-MOF histone acetyltransferase fusion protein in Drosophila}, volume={11}, ISSN={["1471-2199"]}, DOI={10.1186/1471-2199-11-80}, abstractNote={Abstract Background In male Drosophila melanogaster , the male specific lethal (MSL) complex is somehow responsible for a two-fold increase in transcription of most X-linked genes, which are enriched for histone H4 acetylated at lysine 16 (H4K16ac). This acetylation requires MOF, a histone acetyltransferase that is a component of the MSL complex. MOF also associates with the non-specific lethal or NSL complex. The MSL complex is bound within active genes on the male X chromosome with a 3' bias. In contrast, the NSL complex is enriched at promoter regions of many autosomal and X-linked genes in both sexes. In this study we have investigated the role of MOF as a transcriptional activator. Results MOF was fused to the DNA binding domain of Gal4 and targeted to the promoter region of UAS-reporter genes in Drosophila . We found that expression of a UAS-red fluorescent protein (DsRed) reporter gene was strongly induced by Gal4-MOF. However, DsRed RNA levels were about seven times higher in female than male larvae. Immunostaining of polytene chromosomes showed that Gal4-MOF co-localized with MSL1 to many sites on the X chromosome in male but not female nuclei. However, in female nuclei that express MSL2, Gal4-MOF co-localized with MSL1 to many sites on polytene chromosomes but DsRed expression was reduced. Mutation of conserved active site residues in MOF (Glu714 and Cys680) reduced HAT activity in vitro and UAS-DsRed activation in Drosophila . In the presence of Gal4-MOF, H4K16ac levels were enriched over UAS- lacZ and UAS- arm-lacZ reporter genes. The latter utilizes the constitutive promoter from the arm gene to drive lacZ expression. In contrast to the strong induction of UAS-DsRed expression, UAS- arm-lacZ expression increased by about 2-fold in both sexes. Conclusions Targeting MOF to reporter genes led to transcription enhancement and acetylation of histone H4 at lysine 16. Histone acetyltransferase activity was required for the full transcriptional response. Incorporation of Gal4-MOF into the MSL complex in males led to a lower transcription enhancement of UAS- DsRed but not UAS- arm-lacZ genes. We discuss how association of Gal4-MOF with the MSL or NSL proteins could explain our results.}, journal={BMC MOLECULAR BIOLOGY}, author={Schiemann, Anja H. and Li, Fang and Weake, Vikki M. and Belikoff, Esther J. and Klemmer, Kent C. and Moore, Stanley A. and Scott, Maxwell J.}, year={2010}, month={Nov} }
 @article{schiemann_weake_li_laverty_belikoff_scott_2010, title={The importance of location and orientation of male specific lethal complex binding sites of differing affinities on reporter gene dosage compensation in Drosophila}, volume={402}, ISSN={["1090-2104"]}, DOI={10.1016/j.bbrc.2010.10.088}, abstractNote={The male specific lethal (MSL) complex is required for X chromosome dosage compensation in Drosophila. The complex binds to most actively transcribed X-linked genes in males and upregulates expression. High resolution chromatin immunoprecipitation assays have identified over one hundred high affinity binding sites on the X chromosome. One of the first high affinity sites discovered is at cytological location 18D11. The MSL complex binds weakly to a single copy of a 510bp fragment from 18D11 but strongly to a tetramer of the fragment. Here we have investigated the effect of insertion of sites of differing affinities, either upstream or within the transcribed gene, on complex binding and transcription upregulation. Insertion of four copies of the 18D11 fragment upstream or at the 3' end of a reporter gene led to strong MSL complex binding and increased expression in males. In contrast, the MSL complex did not bind consistently to autosomal transgenes that contained a single copy of the 18D11 site upstream of the gene promoter. However, MSL complex binding was observed in all lines if the single 18D11 fragment was inserted into the 3' end of the reporter gene in either orientation. This is consistent with previous studies that showed gene transcription facilitates MSL complex binding. Surprisingly, transcription elevation in males was only observed if the 18D11 fragment was in the forward orientation and only in some lines. Our results suggest that MSL complex binding to weaker sites and transcription enhancement is influenced by gene transcription, binding site orientation and the local chromatin environment. In contrast, strong binding sites do not need to be transcribed to recruit sufficient complex to cause transcription elevation of nearby genes.}, number={4}, journal={BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS}, author={Schiemann, Anja H. and Weake, Vikki M. and Li, Fang and Laverty, Corey and Belikoff, Esther J. and Scott, Maxwell J.}, year={2010}, month={Nov}, pages={699–704} }