Journal Article

An oomycete effector targets a plant RNA helicase involved in root development and defense

Jauneau, Alain, ANR-10-LABX-0041,TULIP,Towards a Unified theory of biotic Interactions: the roLe of environmental, European Project: 766048,MSCA-ITN-2017,PROTECTA, LRSV-Interactions Microbiennes dans la Rhizosphère et les Racines (LRSV-IMRR) ; Laboratoire de Recherche en Sciences Végétales (LRSV) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT), Plateforme TRI FR-AIB ; Fédération de Recherche Agrobiosciences, Interactions et Biodiversité (FR AIB) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre Nat

2022

Overview

Oomycete plant pathogens secrete effector proteins to promote disease. The damaging soilborne legume pathogen Aphanomyces euteiches harbors a specific repertoire of Small Secreted Protein effectors (AeSSPs), but their biological functions remain unknown. Here we characterize AeSSP1256. The function of AeSSP1256 is investigated by physiological and molecular characterization of Medicago truncatula roots expressing the effector. A potential protein target of AeSSP1256 is identified by yeast-two hybrid, co-immunoprecipitation, and fluorescent resonance energy transfer-fluorescence lifetime imaging microscopy (FRET-FLIM) assays, as well as promoter studies and mutant characterization. AeSSP1256 impairs M. truncatula root development and promotes pathogen infection. The effector is localized to the nucleoli rim, triggers nucleoli enlargement and downregulates expression of M. truncatula ribosome-related genes. AeSSP1256 interacts with a functional nucleocytoplasmic plant RNA helicase (MtRH10). AeSSP1256 relocates MtRH10 to the perinucleolar space and hinders its binding to plant RNA. MtRH10 is associated with ribosome-related genes, root development and defense. This work reveals that an oomycete effector targets a plant RNA helicase, possibly to trigger nucleolar stress and thereby promote pathogen infection.

• Publisher: Wiley,CCSD,Wiley Subscription Services, Inc
• Subject: Alfalfa / Aphanomyces / Aphanomyces - physiology / Aphanomyces euteiches / DNA helicase / effectors / energy / Energy transfer / Fluorescence / Fluorescence resonance energy transfer / Gene Expression Regulation, Plant / Genes / Immunoprecipitation / Legumes / Life Sciences / Medicago / Medicago truncatula / Medicago truncatula - genetics / Medicago truncatula - metabolism / Microscopy / MtRH10 / mutants / Nucleic acids / nucleolar stress / Nucleoli / oomycete / Pathogens / plant development / Plant Proteins - genetics / Plant Proteins - metabolism / Plant Roots - metabolism / precipitin tests / protein secretion / Proteins / Ribonucleic acid / Ribosomes / RNA / RNA helicase / RNA helicases / RNA Helicases - genetics / RNA, Plant - metabolism / Root development / Secretion / Vegetal Biology / Yeast / Yeasts