甘蓝型油菜沪油15中BnaRAV-2-HY15转录因子的克隆及表达分析

基于拟南芥RAV类转录因子的序列，通过电子克隆的方法获得甘蓝型油菜的BnaRAV-2基因序列，再利用RT-PCR方法从甘蓝型油菜沪油15中扩增出编码RAV类转录因子基因BnaRAV-2-HY15，并进行了序列和进化分析。结果显示，该转录因子基因长1119 bp，编码372个氨基酸，含有相对保守的AP2结合域和B3结构域，具有典型的植物RAV类转录因子的结构特征。BnaRAV-2-HY15 和AtRAV2具有相似的三维结构。采用半定量RT-PCR方法对基因表达水平进行分析，发现BnaRAV-2-HY15受到PEG、高盐和低温的诱导表达。BnaRAV-2-HY15基因在沪油15盛花和籽粒发育时期的根、茎、叶、花、蕾和荚中均检测不到明显的表达。

CLONING AND EXPRESSION ANALYSIS OF TRANSCRIPTION FACTOR BnaRAV-2-HY15 FROM Brassica napus L.HUYOU 15

The sequences of BnaRAV-2 gene from Brassica napus were obtained by in silico cloning method based on the RAV factor sequence of Arabidopsis, One of RAV family genes, BnaRAV-2-HY15, was isolated by RT-PCR method from B. napus L. cv Huyou15. Then, cDNA and deduced amino acid sequence, phylogenetic tree, and molecular modeling were predicted and analyzed. The coding region of the cloned gene was 1119 bp in length, encoding a 372 amino acids protein. BnaRAV-1-HY15 contained two distinct DNA-binding domains mainly found in higher plants RAV family factors, one AP2 domain together with one B3 domain. BnaRAV-2-HY15 and AtRAV2 had similar three-dimension structure. The results of semi-quantitative RT-PCR analysis for Huyou15 exposed to various treatments demonstrated that the mRNA of gene BnaRAV-2-HY15 was induced by PEG, high-salinity and low-temperature stresses. The gene expression was not detected from the tissues of pod, bud, petal, leaf, stem and root of normally grown Huyou15 plant at period of flowering and seed development.