title: AtPUB19, a U-box E3 ubiquitin ligase, negatively regulates abscisic acid and drought responses in Arabidopsis thaliana.
abstract: 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.
authors.affiliation: College of Agriculture/The Key Laboratory of Oasis Eco-agriculture, Shihezi University, Shihezi, Xinjiang 832003, China.
authors.forename: Yong-Chang
authors.initials: YC
authors.lastname: Liu
authors.forename: Yao-Rong
authors.initials: YR
authors.lastname: Wu
authors.forename: Xia-He
authors.initials: XH
authors.lastname: Huang
authors.forename: Jie
authors.initials: J
authors.lastname: Sun
authors.forename: Qi
authors.initials: Q
authors.lastname: Xie
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics* / Q000502:physiology; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics; D009154:Mutation; D013312:Stress, Physiological / Q000235:genetics*; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000040:Abscisic Acid; D044767:Ubiquitin-Protein Ligases