@article{smith_robertson_yates_nielsen_brown_dean_payne_2008, title={The effect of temperature on Natural Antisense Transcript (NAT) expression in Aspergillus flavus}, volume={54}, ISSN={0172-8083 1432-0983}, url={http://dx.doi.org/10.1007/s00294-008-0215-9}, DOI={10.1007/s00294-008-0215-9}, abstractNote={Naturally occurring Antisense Transcripts (NATs) compose an emerging group of regulatory RNAs. These regulatory elements appear in all organisms examined, but little is known about global expression of NATs in fungi. Analysis of currently available EST sequences suggests that 352 cis NATs are present in Aspergillus flavus. An Affymetrix GeneChip microarray containing probes for these cis NATs, as well as all predicted genes in A. flavus, allowed a whole genome expression analysis of these elements in response to two ecologically important temperatures for the fungus. RNA expression analysis showed that 32 NATs and 2,709 genes were differentially expressed between 37 degrees C, the optimum temperature for growth, and 28 degrees C, the conducive temperature for the biosynthesis of aflatoxin (AF) and many other secondary metabolites. These NATs correspond to sense genes with diverse functions including transcription initiation, carbohydrate processing and binding, temperature sensitive morphogenesis, and secondary metabolism. This is the first report of a whole genome transcriptional analysis of NAT expression in a fungus.}, number={5}, journal={Current Genetics}, publisher={Springer Science and Business Media LLC}, author={Smith, Carrie A. and Robertson, Dominique and Yates, Bethan and Nielsen, Dahlia M. and Brown, Doug and Dean, Ralph A. and Payne, Gary A.}, year={2008}, month={Sep}, pages={241–269} }
 @article{smith_woloshuk_robertson_payne_2007, title={Silencing of the aflatoxin gene cluster in a diploid strain of Aspergillus flavus is suppressed by ectopic aflR expression}, volume={176}, ISSN={["1943-2631"]}, DOI={10.1534/genetics.107.073460}, abstractNote={Aflatoxins are toxic secondary metabolites produced by a 70-kb cluster of genes in Aspergillus flavus. The cluster genes are coordinately regulated and reside as a single copy within the genome. Diploids between a wild-type strain and a mutant (649) lacking the aflatoxin gene cluster fail to produce aflatoxin or transcripts of the aflatoxin pathway genes. This dominant phenotype is rescued in diploids between a wild-type strain and a transformant of the mutant containing an ectopic copy of aflR, the transcriptional regulator of the aflatoxin biosynthetic gene cluster. Further characterization of the mutant showed that it is missing 317 kb of chromosome III, including the known genes for aflatoxin biosynthesis. In addition, 939 kb of chromosome II is present as a duplication on chromosome III in the region previously containing the aflatoxin gene cluster. The lack of aflatoxin production in the diploid was not due to a unique or a mis-expressed repressor of aflR. Instead a form of reversible silencing based on the position of aflR is likely preventing the aflatoxin genes from being expressed in 649 x wild-type diploids. Gene expression analysis revealed the silencing effect is specific to the aflatoxin gene cluster.}, number={4}, journal={GENETICS}, author={Smith, Carrie A. and Woloshuk, Charles P. and Robertson, Dominique and Payne, Gary A.}, year={2007}, month={Aug}, pages={2077–2086} }