Isolation and characterization of two pathogen- and salicylic acid-induced genes encoding WRKY DNA-binding proteins from tobacco.

摘要: A pathogen- and salicylic acid (SA)-induced DNA-binding activity has been recently identified in tobacco that is related to a previously class of WRKY proteins. To identify members the gene family associated with this activity, we have attempted isolate those genes are induced by pathogen infection. Using domain-specific differential display procedure, isolated two genes, tWRKY3 tWRKY4, rapidly resistant plants after infection mosaic virus (TMV). Both tWRK3 tWRKY4 encode proteins single domain contain conserved WRKYGQK sequence. Unlike other Cys2His2 zinc motif, appear Cys2HisCys motif. Nonetheless, both capable binding DNA molecules W-box (TTGAC) element recognized Expression could be not only TMV but also SA or its biologically active analogues inducing pathogenesis-related enhanced resistance. Interestingly, induction was still observed expressing bacterial salicylate hydroxylase (nahG), although levels appeared reduced. Identification SA-induced encoding should facilitate future studies on regulation functions novel group