title: DEAD-box RNA helicases and epigenetic control of abiotic stress-responsive gene expression.
abstract: Plant responses to abiotic stresses are controlled by a complex tier of epigenetic, transcriptional and post-transcriptional regulation. We have provided evidence that the DEAD-box RNA helicases, STRESS RESPONSE SUPPRESSOR (STRS) 1 and STRS2 are negative regulators of Arabidopsis thaliana stress-responsive transcription factors. Using GFP-STRS fusion proteins, we have demonstrated that the STRSs are localized to the nucleolus and chromocenters, and are rapidly removed to the nucleoplasm upon application of various abiotic stresses. The STRSs appear to act via RNA-directed DNA methylation to suppress Arabidopsis stress responses; this repressive epigenetic mechanism is abrogated by abiotic stress eventually leading to an open chromatin structure allowing expression of stress-responsive genes.
authors.affiliation: a French Associates Institute for Agriculture and Biotechnology of Drylands; Jacob Blaustein Institutes for Desert Research ; Ben-Gurion University of the Negev ; Midreshet Ben-Gurion , Israel.
authors.forename: Simon
authors.initials: S
authors.lastname: Barak
authors.forename: Narendra
authors.initials: N
authors.lastname: Singh Yadav
authors.forename: Asif
authors.initials: A
authors.lastname: Khan
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D053487:DEAD-box RNA Helicases / Q000235:genetics / Q000378:metabolism*; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D008954:Models, Biological; D013312:Stress, Physiological / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; C525658:STRS1 protein, Arabidopsis; C525659:STRS2 protein, Arabidopsis; D053487:DEAD-box RNA Helicases
keywords: ABA, abscisic acid; Arabidopsis thaliana; DEAD-box RNA helicases; RNA-directed DNA methylation; RdDM, RNA-directed DNA methylation.; STRS, STRESS RESPONSE SUPPRESSOR; abiotic stress; epigenetic gene silencing; nucleolus