Isolation and characterization of novel transcription factor CBFs/DREBs in Triticum aestivum L. containing conserved EREBP/AP2 domain.

摘要

The transcription factors CBFs/DREBs have been shown to specifically bind to crs-acting element DRE/CRT (A/GCCGAC), which is present in the promoter regions of a large number of abiotic-inducible genes encoding stress-related proteins. Four orthologues (W2/5/18/23) of the Arabidopsis transcription factor CBFs/DREBs were isolated from the Triticum aestivum L. by screening cDNA library derived from drought-induced wheat leaves using conserved EREBP/AP2 domain as a probe. Deduced amino acid sequences suggest that W2, W5, W18 and W23 encode putative DREB proteins with conserved EREBP/AP2 domain. Using the BLAST program in GenBank, W2 is detected to be 58% homologous with putative EREBP/AP2 domain transcription factor from Oryza sativa (gi 19920190). Results also show that W5 and W18 are 98% similar with each other, and W23 is 83% identical to HvDRF1.3, transcription factor from Hordeum vulgare (gi27960760). While the similarity between W2/5/18/23 and TaDREBl, the only CBF/DREB from T. aestivum L., is less than 39%, so W2/5/18/23 are deduced to be novel DREB genes in T. aestivum L..