CmWRKY1 enhances the dehydration tolerance of chrysanthemum through the regulation of ABA-aociated genes

Abstract

WRKY transcription factors serve as antagonistic or synergistic regulators in a variety of abiotic stre responses in plants. Here, we show that CmWRKY1, a member of the group IIb WRKY family isolated from Chrysanthemum morifolium, exhibits no transcriptional activation in yeast cells. The subcellular localization examination showed that CmWRKY1 localizes to the nucleus in vivo. Furthermore, CmWRKY1-overexpreing transgenic lines exhibit enhanced dehydration tolerance in response to polyethylene glycol (PEG) treatment compared with wild-type plants. We further confirmed that the transgenic plants exhibit suppreed expreion levels of genes negatively regulated by ABA, such as PP2C, ABI1 and ABI2, and activated expreion levels of genes positively regulated by ABA, such as PYL2, SnRK2.2, ABF4, MYB2, RAB18, and DREB1A. Taken together, our results indicate that CmWRKY1 plays an important role in the response to drought in chrysanthemum through an ABA-mediated pathway.