A cellular outlook of galls induced by root-knot nematodes in the model host Arabidopsis thaliana

Root-knot nematodes are phytopathogens that cause hypertrophy and hyperplasia of cells of the vascular cylinder resulting in gall formation. These root swellings contain giant-feeding cells, which in order to develop must induce the mitotic cell cycle and the endocycle resulting in multinucleation and nuclei enlargement. Nematode-induced giant cells in the model host Arabidopsis thaliana allows us to perform deep fundamental research which has identified a number of cell cycle genes driving giant cell development. These include cell cycle activating genes as well as inhibitors which are responsible to stimulate and control gall development. Our studies have demonstrated that giant cells induced in Arabidopsis can be used as a model to better understand how the cell cycle functions not only in this highly specialized plant cell type but also in uninfected plant cells. Also the studies performed on the cytoskeleton in giant-feeding cells have shown the relevance of cytoskeleton remodeling in these cells. Nematodes induce cytoskeleton breakdown most likely to allow efficient feeding. The fundamental knowledge gathered can now be used by nematologists to design novel strategies to fight against this widespread pest and thereby contributing to a more sustainable agriculture.