INTERACTION OF Trichoderma atroviride WITH Arabidopsis thaliana ROOTS: OPTIMIZING A HYDROPONIC SYSTEM FOR THE STUDY OF THE SECRETOME.

Secreted proteins are central to the molecular dialog between fungi and their plant hosts (Lamdan et al., 2015). Roots secrete low- and high-molecular-weight proteins and small molecules into the rhizosphere to modulate communication (Denis et al., 2009, Plant Soil). Root cell wall proteomics has been performed on the model plant A. thaliana, to identify new secreted proteins that contribute to understanding the biology of root related to plant defense (Mathieu et al., 2015, Plant Methods). Studies in maize roots in interaction with Trichoderma virens identified some apoplastic proteins, as glycosyl hydrolases and peroxidases, that may lead to a symbiotic relationship by suppression of plant immune pathways (Mendoza et al. ,2018, Frontiers in Plant Sci). However, one of the difficulties to work with plant proteins is to get enough tissue, because depending on the organelle, plant protein is about 20 times less since thick cell walls largely contribute to the total biomass (Jorrin-Novo et al., 2014, Meth Molec Biol). An efficient hydroponic device was previously developed in our lab to collect secretome of Trichoderma interacting with maize roots, so here we optimized a system for A. thaliana in hydroponic conditions. We present a design of hydroponics to collect secreted proteins, adapted for Arabidopsis thaliana. This system offers advantages for cultivation of plants throughout their entire life cycle, easy access to collect roots and media. This Arabidopsis hydroponic system makes it possible to collect large root samples, leaves, and secreted protein in the media. Therefore, this system can be used as a valuable tool in proteomics of fungal-plant interactions.

Keywords: Trichoderma atroviride, Arabidopsis thaliana, Hydroponic, Secretome.