Overexpression of AtMYB52 Confers ABA Hypersensitivity and Drought Tolerance

• DOI: 10.1007/s10059-011-0300-7
• Publication Date: 2011-03-11T17:12:30Z
• Authors: Min Young Park; Jung-youn Kang; Soo Young Kim
• Keywords: 0301 basic medicine; 03 medical and health sciences; Phenotype; Arabidopsis Proteins; Gene Expression Regulation, Plant; Arabidopsis; Abscisic Acid; Droughts

We carried out activation tagging screen to isolate genes regulating abscisic acid (ABA) response. From the screen of approximately 10,000 plants, we isolated ca 100 ABA response mutants. We characterized one of the mutants, designated ahs1, in this study. The mutant is ABA-hypersensitive, and AtMYB52 was found to be activated in the mutant. Overexpression analysis to recapitulate the mutant phenotypes demonstrated that ATMYB confers ABA-hypersensitivity during postgermination growth. Additionally, AtMYB52 overexpression lines were drought-tolerant and their seedlings were salt-sensitive. Changes in the expression levels of a few genes involved in ABA response or cell wall biosynthesis were also observed. Together, our data suggest that AtMYB52 is involved in ABA response. Others previously demonstrated that AtMYB52 regulates cell wall biosynthesis; thus, our results imply a possible connection between ABA response and cell wall biosynthesis.