Rhizosphere microbiome recruitment by plants : Expansion of microRNA roles

An innovative strategy for sustainable ‘green’ agriculture to substitute to the use of fertilizer and pesticides is urgently needed.

In plants, the micro-organisms of the rhizosphere associated with the plant root, are known to affect the physiology and the development of the plant.

Therefore, modulating the microbiome of the rhizosphere may be a promising strategy to achieve sustainable green agriculture.

Recent research has shown that miRNAs secreted by eukaryotic host can act as an interkingdom signal to impact the viability of specific micro-organisms, including pathogens.

Therefore, this EU proposal aims to explore the impact of miRNAs secreted by the plant root on the composition and gene expression of the rhizosphere microbiome.

The objectives are (1) to identify specific secreted miRNAs that may influence the rhizosphere microbiome composition, (2) to analyse the biological features of the secreted miRNA-containing vesicles, (3) to understand how specific secreted miRNAs influence microbiome gene expression, (4) to determine in natura the repertoire of miRNA and associated microbiome for selected plants of agricultural interest.

A combination of metagenomic and transcriptomic analysis of the soil rhizosphere from plant models (Arabidopsis thaliana and Brachypodium distachyon) under laboratory condition, as well as with selected plants of agricultural interest in natura conditions will be undertaken.

The spectrum of activity of specific, or combinations of, secreted miRNAs will be also explored using A. thaliana knock-out mutants, or by perturbation of the secreted miRNAs in the WT plant using a strategy based on innovative miPEP technology.

Ultimately this research can have application for miRNA-based modulation of the microbiomes of halobionts, including plants of agricultural interest.

The unique complementarity of expertise between the fellow and his supervisor, completed by a well designed training program, will allow him to take up this challenge.