关键词: 铃铛刺；DREB转录因子；RACE技术；酵母单杂交；半定量RT\, PCR；亚细胞定位

Abstract:

In this study, a full\|length cDNA sequence of DREB transcription factor gene, HhDREB2 (Genbank No.: EU872018), was isolated from Halimodendron halodendron. Voss by homology\|based cloning and RACE (rapid amplification of cDNA end) technology. Sequence analysis showed that the cDNA sequence is 873 bp without introns and has a maximum open reading frame from 108 to 626 bp, encoding 172 amino acid residues. Molecular weight of the gene encoding protein is 19.702 kDa, isoelectric point is 8.92. Phylogenetic tree and homologous sequence alignment analyses indicated that this protein contained a typical AP2/ERF conservative domain, and was most closely related to soybean GmDREB2, belonging to the A5 subgroups. Yeast one\|hybrid experiment demonstrated that HhDREB2 gene encodes a transcription activator. In addition, subcellular localization analysis of a construct with the transient expression vector of the HhDREB2 gene showed that the HhDREB2 protein was localized in the nucleus. The expression level of HhDREB2 gene was greatly induced by high salt, drought and low temperature through semi\|quantitative RT\|PCR, and had no significant change with GA3, NAA, ABA and 6BA treatments.

Key words: Halimodendron halodendron. Voss, DREB transcription factor, RACE technology, yeast one\, hybrid, semi\, quantitative RT\, PCR, subcellular localization