Identification of upstream transcription factors and an interacting PP2C protein of dehydrin WZY2 gene in wheat.

As functional proteins dehydrins are found in many maturing seeds and vegetable tissue under adverse environmental conditions. However, the regulation of dehydrin expression remains unclear.To explore regulatory mechanisms of wheat dehydrin WZY2 expression under abiotic stresses, we constructed a cDNA library from PEG- and cold-treated wheat seedlings and performed yeast one-hybrid assay and yeast two-hybrid assay to identify the upstream transcription factors and protein interacting with dehydrin WZY2 gene. Yeast one-hybrid assay illustrated that bHLH49-like (GenBank NO. XM_020296294), zinc finger A20 and AN1 domain-containing stress-associated protein 6-like (GenBank NO. XM_020341647), and bHLH47-like (GenBank NO. XM_020313116) proteins can bind and interact with the promoter of the WZY2, these sequences are Aegilops tauschii transcription factors, the diploid progenitor of the D genome of hexaploid wheat (Triticum aestivum, genomes AABBDD). Real-time PCR analyzes unraveled the stress responsive expression of XM_020296294, XM_020341647, and XM_020313116 in wheat. XM_020296294 and XM_020341647 showed a similar expression patterns with WZY2. Yeast two-hybrid assay indicated that PP2C (GenBank NO. XM_020293398) protein can interact with WZY2. These results provided evidences that WZY2 could be positively regulated by XM_020296294 and XM_020341647 transcription factors, and WZY2 may also play an important role in the ABA signaling pathway through interaction with PP2C to regulate stress-responsive genes expression in wheat. The obtained results contribute for provide a better understanding of the regulatory mechanism of dehydrin expression under abiotic stresses in wheat.