Modulation of Alternative Splicing of Host mRNAs by root-knot nematodes – MASH
Plant-parasitic nematodes have a major impact on global food production with an estimated annual cost of about €100 billion worldwide. Root-knot nematodes (Meloidogyne spp.) alone are responsible for 5% of the global crop losses. These soilborne root pathogens have a worldwide distribution, can infect most all cultivated plants, and are particularly damaging for vegetables (tomato, pepper and cucumber). For decades, wide-spectrum agrochemical control agents (nematicides) have been used. Because of their toxicity and harmful impact on the environment, most of these pesticides have been or will be banned worldwide. New control strategies must be developed to meet consumers demand for safer food production and more durable environmental approaches. Plant natural resistances to control nematodes is an efficient alternative to pesticides. However, few resistance sources were identified in a limited number of crops and an increasing number of field nematode populations have already overcome these host resistances. The MASH project would provide a comprehensive knowledge of the biological processes manipulated by root-knot nematodes that are essential to the development of the disease, and could lead to the development of new control strategies. During infection, root-knot nematodes secrete a cocktail of molecules, named effectors, to induce specialised multinucleate feeding cells, named giant cells, essential for the nematode development and reproduction. Transcriptome analyses revealed a major reprogramming of gene expression during giant cell formation, associated with tight regulation of nuclear division, cell growth and plant hormone pathways. Recently, root-knot nematodes have been shown to modulate a process named alternative splicing in giant cells in the model plant Arabidopsis. Alternative splicing enables a precursor messenger RNA (mRNA) to generate not only one, but two or several mature mRNAs, giving rise to a set of mRNA sequences from a single parental gene. It occurs by rearranging the pattern of intron and exon elements. Alternative splicing largely contributes to gene expression regulation and proteome diversity, in particular during plant adaptation to stresses. MASH aims at a better understanding of plant responses to root-knot nematode infection focusing on the third most consumed vegetable worldwide, tomato. Our objectives are to (i) study the prevalence of genome-wide alternative splicing changes during root-knot nematode infection, (ii) characterize conserved root-knot nematode nuclear secreted effectors modulating alternative splicing, and (iii) identify and functionally characterize plant targets of splicing regulatory effectors and key alternative splicing-regulated genes. MASH is a multidisciplinary project including bioinformatics, RNAomics and phytopathology. MASH should significantly improve our knowledge of the role of alternative splicing in plant responses to parasitic nematodes. The characterisation of target plant genes essential for root-knot nematode infection and the identification of mutants/variants reducing nematode infection, may provide innovative control strategies against these pests.
Monsieur Bruno Favery (Institut national de recherche pour l’agriculture, l’alimentation et l’environnement – Centre de Recherche PACA /Institut Sophia Agrobiotech)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
INRAE PACA / ISA Institut national de recherche pour l’agriculture, l’alimentation et l’environnement – Centre de Recherche PACA /Institut Sophia Agrobiotech
INRAE / IPS2 Institut national de recherche pour l’agriculture, l’alimentation et l’environnement / Institut des Sciences des Plantes de Paris Saclay
Help of the ANR 636,976 euros
Beginning and duration of the scientific project: December 2021 - 48 Months