Abstract：WRKY transcription factor is a zinc finger protein unique to plants. Based on the transcriptome data of tartary buckwheat, a WRKY transcription factor gene FtWRKY10 was cloned in this study. Sequence analysis results showed that FtWRKY10 was located on chromosome 5 of tartary buckwheat genome, its DNA length was 4 303 bp, which contained 6 exons and 5 introns, and its ORF was 1 647 bp. The deduced FtWRKY10 protein was a classic WRKY transcription factor of type I, and it had the closest phylogenetic relationship with AtWRKY20 of Arabidopsis thaliana. qRT-PCR showed that its expression was induced by drought stress in tartary buckwheat. Molecular identification results showed that FtWRKY10 protein showed transcriptional activation activity in yeast and located in the nucleus of transgenic Arabidopsis thaliana cells. The transcription factor could specifically bind with its target DNA motif of W-box in yeast and plant cells and initiate the expression of the reporter genes, respectively. In Arabidopsis, overexpression of FtWRKY10 could enhance the tolerance of Arabidopsis germination to drought and ABA treatments. Under drought stress, the overexpression of FtWRKY10 could increase the content of chlorophyll and proline, the activity of SOD (Superoxide dismutase), POD (Peroxidase) and CAT (Catalase), and also up regulate the expression of stress resistance related genes of responsive to dehydration protein genes (RD29A, RD29B, and RD22), responsive to ABA protein gene RAB18, and serine/threonine protein kinase gene KIN1. For conclusion, the FtWRKY10 encodes a type I WRKY transcription factor related to drought tolerance. This study could provide strategies for exploiting and utilizing the excellent stress resistance traits from tartary buckwheat, and supply basic materials for further enriching the functions of WRKY family.
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