DREB1/CBF类转录因子在植物抵抗外界胁迫上起重要作用,利用这些基因改良作物抗逆性具有重要意义。本研究在白菜中分离到一个DREB类转录因子基因BpDREB1 (EF219470)。该基因序列全长647 bp,推测编码蛋白含213个氨基酸,相对分子量为23 kD,理论等电点为5.11,与白菜中该类转录因子序列同源性为94%。进化树表明,BpDREB1属于DREB亚家族中A1亚族。基因的诱导表达模式分析显示,BpDREB1被低温强烈、迅速诱导表达,并对干旱胁迫也有一定程度的响应,但对高盐处理几乎没有响应。过表达BpDREB1的转基因拟南芥经低温诱导后,其体内可溶性糖及脯氨酸含量大幅度提高。以上结果显示BpDREB1转录因子基因具有家族成员基因结构的特征,在低温、干旱应答途径中起重要作用。
DREB1/CBF transcription factors play an important role in plant stress tolerance, and one of important significance to gain stress-tolerant crops by transgenic technologies. In this study, a DREB-like gene, named BpDREB1 (accession No. EF219470), was cloned from Chinese cabbage. The BpDREB1 cDNA was 647 bp in length, and encoded protein of 213 amino acids with an predicted molecular weight of 23 kDand a isoelectric point of5.11, and shared 94% similarity with other DREB transcription factor from Chinese cabbage. On the basis of multiple sequence alignment and phylogenetic analysis, BpDREB1 was classified in A-1 group of the DREB family. The expression patterns analysis indicated that BpDREB1 was strongly up-regulated at low temperature, also responded to dehydration.However, the expression of BpDREB1 was not affected by high salinity. The expression pattern of BpDREB1 was the same as that of other DREB transcription factors in A-1 group. Overexpression of BpDREB1 greatlyincreased the contents of total soluable sugar andfree prolinein transgenic Arabidopsis plants, demonstrating that transgenic Arabidopsis induced the expression of soluable sugar and prolin related genes to enhance the tolerance to stress. These results suggest that BpDREB1 from Chinese cabbage has the typical characteristic of DREB transcription factors, and functions under the stress conditions including low temperature and drought.