The RdDM Pathway Is Required for Basal Heat Tolerance in Arabidopsis

• Published in: Molecular plant 2013-03, Vol.6 (2), p.396-410
• Main Authors: Popova, Olga V., Dinh, Huy Q., Aufsatz, Werner, Jonak, Claudia
• Format: Article
• Language: English
• Subjects: Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; DNA Methylation - genetics; DNA Transposable Elements - genetics; DNA-Directed RNA Polymerases - genetics; DNA-Directed RNA Polymerases - metabolism; DNA甲基化; Epigenesis, Genetic; heat stress; Histone Deacetylases - genetics; Histone Deacetylases - metabolism; Hot Temperature; Mutation; Plant Proteins - genetics; read-through transcription; RNA, Plant - genetics; RNA-directed DNA methylation; RNA聚合酶; siRNA; transposons; Up-Regulation; 基础; 拟南芥; 热应激反应; 组蛋白脱乙酰基酶; 耐热性
• ISSN: 1674-2052; 1752-9867
• DOI: 10.1093/mp/sst023

Heat stress affects epigenetic gene silencing in Arabidopsis. To test for a mechanistic involvement of epige-netic regulation in heat-stress responses, we analyzed the heat tolerance of mutants defective in DNA methylation, his-tone modifications, chromatin-remodeling, or siRNA-based silencing pathways. Plants deficient in NRPD2, the common second-largest subunit of RNA polymerases IV and V, and in the Rpd3-type histone deacetylase HDA6 were hypersensi- tive to heat exposure. Microarray analysis demonstrated that NRPD2 and HDA6 have independent roles in transcriptional reprogramming in response to temperature stress. The misexpression of protein-coding genes in nrpd2 mutants recover-ing from heat correlated with defective epigenetic regulation of adjacent transposon remnants which involved the loss of control of heat-stress-induced read-through transcription. We provide evidence that the transcriptional response to temperature stress, at least partially, relies on the integrity of the RNA-dependent DNA methylation pathway.