Cloning And Expression Analysis Of DREB Transcription Factor Gene In Triticum Aestivum "Jinmai47"

Growth and development of plant and environmental factors has a close relationship. In recentyears, with the continuous deterioration of the environment, abiotic stresses, such as drought, lowtemperature, high temperature and high salt, appear more and more frequently, which restrictedthe growth and yield of plantsseverely. The environmental stress factors could induce a series ofphysiological and biochemical changes inplants. It is committed by all means to improve theresistance of plants.One kind of proteins calledtranscription factors can specifically bind the cis-elements in thepromoter region of eukaryotic genes, and regulate transcriptions of a series of downstream genesthrough their interactions with cis-elements or related proteins. AP2/EREBP transcription factorsare unique to plants, plays an important role in the response to the adjustment of adversity stress,have been cloned from a variety of crops. Current research focuses are on DREB, AP2and ERFsubfamilies. DREB transcription factors are a class of plant stress stress response importantprotein.1. The research using homologous cloning technology and RACE, under the variousstressesfrom Variety Jinmai47of wheat (Triticum aestivum L.) isolated certain genes contain aconserved AP2domain, complete ORF belong to DREB transcription factor gene family. The testobtained four kinds of ORF length. They are648bp,834bp,837bp and876bp.2. Jinmai47has excellent drought stress resistance, so to select TaDREB2, which obtainedunder drought stress to research gene expression characteristics analysis and functionalverification. The length of TaDREB2gene is1098bp. Sequence analysis indicated that TaDREB2contains an ORF of834bp, which encodes277amino acid sequence.The molecular weight of thisprotein is30.187kD, the theoretical isolectric point is5.733, wherein the strongly basic aminoacids is38, strongly acidic amino acids is45, hydrophobic amino acids is75, polar amino acids is70.3. Bioinformatics analysis results showed that the gene encodes a protein without atrans-membrane domain and a signal peptide.It was localized in the nucleus and belonged tohydrophily protein.4. By semi-quantitative RT-PCR method, under drought stress, the analysis of geneexpressioncharacteristics showed that, the gene expressed in the untreatedmaterial, and the amountof gene expression was significantly increased at2h and6h,when expression reached maximumexpression began to decrease after8h.5. Prokaryotic expression vector pET-30a fused with TaDREB2sequence induced by IPTG,expressed a36.1kD protein, the highest expression level is at9h.6. Eukaryotic expression vector pBI121fused with TaDREB2sequence.