Abstract
WRKY proteins are transcription factors that are unique to plants. A number of studies have shown that WRKY proteins have regulatory functions in plant response to pathogen infection. Done et al. (2003) reported that WRKY40 (At1g80840) gene was induced by treatment of salicylic acid. In this study, we identified that WRKY40 is rapidly induced by methyl-jasmonic acid, abscisic acid, and ethylene. cDNA microarray and Northern blot analyses showed that WRKY40 gene is induced by drought, high-salt, and low temperature stresses. These results indicate that WRKY40 is the gene that involves in not only biotic stresses but also abiotic stresses. To study biochemical function of WRKY40, we constructed the knockout and the overexpressor mutants in Arabidopsis. We will discuss the role of WRKY40 in stress responsive gene expression.
