Vitis vinifera VvWRKY13 is an ethylene biosynthesis-related transcription factor

Abstract

A novel transcription factor VvWRKY13 was cloned from Vitis vinifera and found functioning in ethylene biosynthesis pathway by mediating ACS2 and ACS8 expression. Grapevine is one of the most economically important plants, and ethylene is a plant hormone related with its growth, development, abiotic and biotic resistance. Until now, the regulators and their mechanism of ethylene biosynthesis are still not well understood. We have cloned a novel gene from a grapevine cultivar 'Zuoyouhong' and named it VvWRKY13. By qRT-PCR analysis, VvWRKY13 was found to be ubiquitously expressed in the leaf, stem, flower, fruit, and root tissues, indicating that it is probably involved in numerous processes of grapevine growth and development. Overexpression of VvWRKY13 in Arabidopsis leads to constitutive triple responses and improved ethylene production. Bioinformatics analysis indicated that the promoters of ACC synthase genes ACS2 and ACS8 contain WRKYs specific binding element W-box. As a result, the expression of ACS2 and ACS8 was found to be increased significantly in VvWRKY13 overexpression lines. Together, these data reveal that the novel transcription factor VvWRKY13 is likely involved in ethylene biosynthesis by the regulation of ACS2 and ACS8 expression.