AtPUB19, a U-Box E3 Ubiquitin Ligase, Negatively Regulates Abscisic Acid and Drought Responses in Arabidopsis thaliana

• Published in: Molecular plant Vol. 4; no. 6; pp. 938 - 946
• Main Authors: Liu, Yong-Chang, Wu, Yao-Rong, Huang, Xia-He, Sun, Jie, Xie, Qi
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.11.2011; Oxford University Press; Cell Press
• Subjects: ABA; ABA诱导; Abscisic acid; Abscisic Acid - pharmacology; Arabidopsis; Arabidopsis - drug effects; Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - physiology; Drought resistance; drought stress; Droughts; Flowers & plants; Gene Expression Regulation, Plant - drug effects; Gene Expression Regulation, Plant - genetics; Hypersensitivity; Mutation; Proteins; Stress, Physiological - genetics; U-box; Ubiquitin-Protein Ligases - genetics; Ubiquitin-Protein Ligases - metabolism; U型; 反应; 干旱; 拟南芥; 泛素连接酶; 脱落酸; 负调控; U-box; ABA; drought stress; Arabidopsis
• ISSN: 1674-2052; 1752-9867; 1752-9867
• DOI: 10.1093/mp/ssr030

Ubiquitination is an important protein post-translational modification, which is involved in various cellular processes in higher plants, and U-box E3 ligases play important roles in diverse functions in eukaryotes. Here, we describe the functions of Arabidopsis thaliana PUB19 (AtPUB19), which we demonstrated in an in vitro assay to encode a U-box type E3 ubiquitin ligase. AtPUB19 was up-regulated by drought, salt, cold, and abscisic acid (ABA). Down-regulation of AtPUB19 led to hypersensitivity to ABA, enhanced ABA-induced stomatal closing, and enhanced drought tolerance, while AtPUB19 overexpression resulted in the reverse phenotypes. Molecular analysis showed that the expression levels of a number of ABA and stress marker genes were altered in both AtPUB19 overexpressing and atpub19-1 mutant plants. In summary, our data show that AtPUB19 negatively regulates ABA and drought responses in A. thaliana.