Heat-Inducible Transcription Factor HsfA2 Enhances Anoxia Tolerance in Arabidopsis

• Published in: Plant physiology (Bethesda) Vol. 152; no. 3; pp. 1471 - 1483
• Main Authors: Banti, Valeria, Mafessoni, Fabrizio, Loreti, Elena, Alpi, Amedeo, Perata, Pierdomenico
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Biologists 01.03.2010
• Subjects: Acclimatization; Anoxia; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biological and medical sciences; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; ENVIRONMENTAL STRESS AND ADAPTATION TO STRESS; Fundamental and applied biological sciences. Psychology; Gene Expression Profiling; Gene Expression Regulation, Plant; Genes; Heat Shock Transcription Factors; Heat tolerance; Heat-Shock Proteins - genetics; Heat-Shock Proteins - metabolism; Hot Temperature; Hydrogen Peroxide - pharmacology; Hypoxia; Messenger RNA; Oxidative stress; Oxygen; Plant physiology and development; Plant Proteins - genetics; Plant Proteins - metabolism; Plants; RNA, Plant - genetics; Seedlings; Stress, Physiological; Submergence; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Arabidopsis thaliana; Heat; Anoxia; Plant physiology; Cruciferae; Dicotyledones; Angiospermae; Tolerance; Spermatophyta; Experimental plant; Transcription factor
• ISSN: 0032-0889; 1532-2548; 1532-2548
• DOI: 10.1104/pp.109.149815

Anoxia induces several heat shock proteins, and a mild heat pretreatment can acclimatize Arabidopsis (Arabidopsis thaliana) seedlings to subsequent anoxic treatment. In this study, we analyzed the response of Arabidopsis seedlings to anoxia, heat, and combined heat + anoxia stress. A significant overlap between the anoxic and the heat responses was observed by whole-genome microarray analysis. Among the transcription factors induced by both heat and anoxia, the heat shock factor A2 (HsfA2), known to be involved in Arabidopsis acclimation to heat and to other abiotic stresses, was strongly induced by anoxia. Heat-dependent acclimation to anoxia is lost in an HsfA2 knockout mutant (hsfa2) as well as in a double mutant for the constitutively expressed HsfA1a/HsfA1b (hsfA1a/1b), indicating that these three heat shock factors cooperate to confer anoxia tolerance. Arabidopsis seedlings that overexpress HsfA2 showed an increased expression of several known targets of this transcription factor and were markedly more tolerant to anoxia as well as to submergence. Anoxia failed to induce HsfA2 target proteins in wild-type seedlings, while overexpression of HsfA2 resulted in the production of HsfA2 targets under anoxia, correlating well with the low anoxia tolerance experiments. These results indicate that there is a considerable overlap between the molecular mechanisms of heat and anoxia tolerance and that HsfA2 is a player in these mechanisms.