Heat stress promotes Arabidopsis AGO1 phase separation and association with stress granule components.
Fiche publication
Date publication
mars 2024
Journal
iScience
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BAUMBERGER Nicolas, Mr HAMMANN Philippe
Tous les auteurs :
Blagojevic A, Baldrich P, Schiaffini M, Lechner E, Baumberger N, Hammann P, Elmayan T, Garcia D, Vaucheret H, Meyers BC, Genschik P
Lien Pubmed
Résumé
In , ARGONAUTE1 (AGO1) plays a central role in microRNA (miRNA) and small interfering RNA (siRNA)-mediated silencing. AGO1 associates to the rough endoplasmic reticulum to conduct miRNA-mediated translational repression, mRNA cleavage, and biogenesis of phased siRNAs. Here, we show that a 37°C heat stress (HS) promotes AGO1 protein accumulation in cytosolic condensates where it colocalizes with components of siRNA bodies and of stress granules. AGO1 contains a prion-like domain in its poorly characterized N-terminal Poly-Q domain, which is sufficient to undergo phase separation independently of the presence of SGS3. HS only moderately affects the small RNA repertoire, the loading of AGO1 by miRNAs, and the signatures of target cleavage, suggesting that its localization in condensates protects AGO1 rather than promoting or impairing its activity in reprogramming gene expression during stress. Collectively, our work sheds new light on the impact of high temperature on a main effector of RNA silencing in plants.
Mots clés
Cell biology, Molecular biology, Plant biology
Référence
iScience. 2024 03 15;27(3):109151