Other Nematode Effectors and Evolutionary Constraints

International audienceLike microbial pathogens, nematodes secrete a repertoire of effectors with diverse functions. In the case of sedentary nematodes, completion of the life cycle requires the maintenance of the biotrophic interaction for several weeks and the induction of a permanent feeding site. These essential processes require fine tuning of plant cell responses. About a hundred candidate effectors have been isolated from nematodes to date that have roles in the invasion of host tissues, evasion of plant defences, suppression of plant defences or manipulation of plant cell fate. Evolutionary studies suggest that several distinct mechanisms have led to the acquisition of these effectors during the evolution of plant parasitism. In addition, since any compound secreted by the parasite can potentially be perceived as nonself by the plant, nematode effectors are subject to selective pressure to escape plant immunity. This chapter reviews the latest findings on nematode effector functions and evolutionary traits