@article{hamamouch_winkel_li_davis_2020, title={Modulation of Arabidopsis Flavonol Biosynthesis Genes by Cyst and Root-Knot Nematodes}, volume={9}, ISSN={["2223-7747"]}, DOI={10.3390/plants9020253}, abstractNote={Although it is well established that flavonoid synthesis is induced in diverse plant species during nematode parasitism, little is known about the regulation of genes controlling flavonol biosynthesis during the plant–nematode interaction. In this study, expression of the Arabidopsis thaliana flavonol-specific transcription factor, AtMYB12, the flavonol synthase genes, AtFLS1, 2, 3, 4, and 5, and the gene encoding the central flavonoid enzyme, chalcone synthase (AtCHS), were examined in plant roots during infection by Heterodera schachtii (sugar beet cyst) and Meloidogyne incognita (root-knot) nematodes. These experiments showed that AtMYB12 was transiently upregulated at 9 dpi in syncytia associated with sugar beet cyst nematode infection and that an Atmyb12-deficient line was less susceptible to the parasite. This suggests that, rather than contributing to plant defense, this gene is essential for productive infection. However, the AtCHS and AtFLS1 genes, which are controlled by AtMYB12, did not exhibit a similar transient increase, but rather were expressly downregulated in syncytia relative to adjacent uninfected root tissue. Genetic analyses further indicated that AtFLS1 contributes to plant defense against Cyst nematode infection, while other AtFLS gene family members do not, consistent with prior reports that these other genes encode little or no enzyme activity. Together, these findings indicate a role of AtMyb12 in promoting the early stages of Cyst nematode infection, while flavonols produced through the action of AtFLS1 are essential for plant defense. On the other hand, a transient induction of AtMYB12 was not observed in galls produced during root-knot nematode infection, but this gene was instead substantially downregulated, starting at the 9 dpi sampling point, as were AtCHS and AtFLS1. In addition, both the AtMYB12- and AtFLS1-deficient lines were more susceptible to infection by this parasite. There was again little evidence for contributions from the other AtFLS gene family members, although an AtFLS5-deficient line appeared to be somewhat more susceptible to infection. Taken together, this study shows that sugar-beet cyst and root-knot nematodes modulate differently the genes involved in flavonol biosynthesis in order to successfully infect host roots and that AtFLS1 may be involved in the plant basal defense response against nematode infection.}, number={2}, journal={PLANTS-BASEL}, author={Hamamouch, Noureddine and Winkel, Brenda S. J. and Li, Chunying and Davis, Eric L.}, year={2020}, month={Feb} }
 @article{hamamouch_li_seo_park_davis_2011, title={Expression of Arabidopsis pathogenesis-related genes during nematode infection}, volume={12}, number={4}, journal={Molecular Plant Pathology}, author={Hamamouch, N. and Li, C. Y. and Seo, P. J. and Park, C. M. and Davis, E. L.}, year={2011}, pages={355–364} }
 @article{manescu_hamamouch_maios_harfouche_doulis_aravanopoulos_2011, title={Linkage mapping of the Mediterranean cypress, Cupressus sempervirens, based on molecular and morphological markers}, volume={10}, number={3}, journal={Genetics and Molecular Research}, author={Manescu, C. and Hamamouch, N. and Maios, C. and Harfouche, A. and Doulis, A. G. and Aravanopoulos, F. A.}, year={2011}, pages={1891–1909} }
 @article{patel_hamamouch_li_hewezi_hussey_baum_mitchum_davis_2010, title={A nematode effector protein similar to annexins in host plants}, volume={61}, ISSN={["1460-2431"]}, DOI={10.1093/jxb/erp293}, abstractNote={Nematode parasitism genes encode secreted effector proteins that play a role in host infection. A homologue of the expressed Hg4F01 gene of the root-parasitic soybean cyst nematode, Heterodera glycines, encoding an annexin-like effector, was isolated in the related Heterodera schachtii to facilitate use of Arabidopsis thaliana as a model host. Hs4F01 and its protein product were exclusively expressed within the dorsal oesophageal gland secretory cell in the parasitic stages of H. schachtii. Hs4F01 had a 41% predicted amino acid sequence identity to the nex-1 annexin of C. elegans and 33% identity to annexin-1 (annAt1) of Arabidopsis, it contained four conserved domains typical of the annexin family of calcium and phospholipid binding proteins, and it had a predicted signal peptide for secretion that was present in nematode annexins of only Heterodera spp. Constitutive expression of Hs4F01 in wild-type Arabidopsis promoted hyper-susceptibility to H. schachtii infection. Complementation of an AnnAt1 mutant by constitutive expression of Hs4F01 reverted mutant sensitivity to 75mM NaCl, suggesting a similar function of the Hs4F01 annexin-like effector in the stress response by plant cells. Yeast two-hybrid assays confirmed a specific interaction between Hs4F01 and an Arabidopsis oxidoreductase member of the 2OG-Fe(II) oxygenase family, a type of plant enzyme demonstrated to promote susceptibility to oomycete pathogens. RNA interference assays that expressed double-stranded RNA complementary to Hs4F01 in transgenic Arabidopsis specifically decreased parasitic nematode Hs4F01 transcript levels and significantly reduced nematode infection levels. The combined data suggest that nematode secretion of an Hs4F01 annexin-like effector into host root cells may mimic plant annexin function during the parasitic interaction.}, number={1}, journal={JOURNAL OF EXPERIMENTAL BOTANY}, author={Patel, Nrupali and Hamamouch, Noureddine and Li, Chunying and Hewezi, Tarek and Hussey, Richard S. and Baum, Thomas J. and Mitchum, Melissa G. and Davis, Eric L.}, year={2010}, month={Jan}, pages={235–248} }
 @article{abad_gouzy_aury_castagnone-sereno_danchin_deleury_perfus-barbeoch_anthouard_artiguenave_blok_et al._2008, title={Genome sequence of the metazoan plant-parasitic nematode Meloidogyne incognita}, volume={26}, ISSN={["1546-1696"]}, DOI={10.1038/nbt.1482}, abstractNote={Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments. This suggests that ancient allelic regions in M. incognita are evolving toward effective haploidy, permitting new mechanisms of adaptation. The number and diversity of plant cell wall-degrading enzymes in M. incognita is unprecedented in any animal for which a genome sequence is available, and may derive from multiple horizontal gene transfers from bacterial sources. Our results provide insights into the adaptations required by metazoans to successfully parasitize immunocompetent plants, and open the way for discovering new antiparasitic strategies.}, number={8}, journal={NATURE BIOTECHNOLOGY}, author={Abad, Pierre and Gouzy, Jerome and Aury, Jean-Marc and Castagnone-Sereno, Philippe and Danchin, Etienne G. J. and Deleury, Emeline and Perfus-Barbeoch, Laetitia and Anthouard, Veronique and Artiguenave, Francois and Blok, Vivian C. and et al.}, year={2008}, month={Aug}, pages={909–915} }
 @article{patel_hamamouch_li_hussey_mitchum_baum_wang_davis_2008, title={Similarity and functional analyses of expressed parasitism genes in Heterodera schachtii and Heterodera glycines}, volume={40}, number={4}, journal={Journal of Nematology}, author={Patel, N. and Hamamouch, N. and Li, C. Y. and Hussey, R. and Mitchum, M. and Baum, T. and Wang, X. H. and Davis, E. L.}, year={2008}, pages={299–310} }