Cloning, Prokaryotic Expression And Sequence Analysis Of DREB-like Gene In Hordeum Violaceum

Abiotic stresses including low temperature, drought and salt could make an considerable impact on crop’s growth and yield. The AP2/EREBP transcription factor is unique for plants, playing important role in responsing abiotic stresses. Recently, lots of AP2/EREBP transcription factors were isolated from kinds of crops. Now, more and more contention is input into some related researches with DREB, AP2 and ERF sub-family. DREB-like transcription factor is important protein for plant to respond abiotic stresses. Thus, in order to improve the resistance of crops and provide candidate genes for molecular breeding with genetic engeering, this research cloned two DREB-like genes from Hordeum violaceum. The methods and results were as follow:1. Utilizing a combination of RACE and homology cloning, to isolated a DREB-like gene from Hordeum violaceum, 1060bp, named as Hvi917DREB2(accession no JQ693159). Sequence analysis indicated that it contains an open reading frame of 792 bp encoding a putative protein with 264 amino acids, and a highly conserved AP2-super family domain. What’s more, untilizing homology cloning isolated another DREB-like gene, 1137bp, containing 837bp ORF, named as Hvi020DREB.2. The bioinformatic analysis indicated that the Hvi917DREB2 doesn’t contain transmembrane domain and signal peptide. Also, it was localized in the nucleus and belonged to hydrophily protein. The protein functions were predicted with informatics online tools. The results shows that it may participate in biosynthesis of confactors, cell envelope, cellular processes, central intermediary metabolism, fatty acid metabolism, regulatory functions and replication.3. Compared with HbDREB2 (accession no AAU29412.1) and DREB1(accession no AER42620.1) from Hordeum brevisubulatum, sequence of Hvi917DREB2 showed 99% identity.4. In addition, cprokaryotic expression vector fused with Hvi917DREB2 sequence was constructed and a 34.5kD DREB-like protein was expressed. The research prepared the foundation for researching the interaction between the DREB transcription factor and DRE cis-element, also provided candidate gene for wheat molecular breeding.