Response of resistant tomato to a population of Meloidogyne incognita (AN1)

International audienc

Response of resistant tomato to a population of Meloidogyne incognita (AN1)

National audienc

The contribution of biotechnology to root-knot nematode control in tomato plants

Special FeatureInternational audienc

Cytological evaluation of pepper lines expressing the root-knot nematode resistance genes Me1 and Me3

International audienc

Feeding cells induced by phytoparasitic nematodes require gamma-tubulin ring complex for microtubule reorganization

Reorganization of the microtubule network is important for the fast isodiametric expansion of giant-feeding cells induced by root-knot nematodes. The efficiency of microtubule reorganization depends on the nucleation of new microtubules, their elongation rate and activity of microtubule severing factors. New microtubules in plants are nucleated by cytoplasmic or microtubule-bound c-tubulin ring complexes. Here we investigate the requirement of c-tubulin complexes for giant feeding cells development using the interaction between Arabidopsis and Meloidogyne spp. as a model system. Immunocytochemical analyses demonstrate that c-tubulin localizes to both cortical cytoplasm and mitotic microtubule arrays of the giant cells where it can associate with microtubules. The transcripts of two Arabidopsis c-tubulin (TUBG1 and TUBG2) and two c-tubulin complex proteins genes (GCP3 and GCP4) are upregulated in galls. Electron microscopy demonstrates association of GCP3 and c-tubulin as part of a complex in the cytoplasm of giant cells. Knockout of either or both c-tubulin genes results in the gene dose-dependent alteration of the morphology of feeding site and failure of nematode life cycle completion. We conclude that the c-tubulin complex is essential for the control of microtubular network remodelling in the course of initiation and development of giant-feeding cells, and for the successful reproduction of nematodes in their plant hosts

Genome sequence of the metazoan plant-parasitic nematode Meloidogyne incognita

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.This article is published as Abad, Pierre, Jérôme Gouzy, Jean-Marc Aury, Philippe Castagnone-Sereno, Etienne GJ Danchin, Emeline Deleury, Laetitia Perfus-Barbeoch et al. "Genome sequence of the metazoan plant-parasitic nematode Meloidogyne incognita." Nature biotechnology 26, no. 8 (2008): 909-915, doi: 10.1038/nbt.1482. Posted with permission.</p

MUSCLE COMPOSITION IN RESPIRATORY ACIDOSIS

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 strategie