棉花bZIP转录因子基因GhbZIP15的克隆与表达分析

Molecular Cloning and Expression of a b ZIP Transcription Factor Gene Ghb ZIP15 in Cotton(Gossypium hirsutum L.)

b ZIP转录因子在植物抵御各种逆境胁迫中有重要作用。本研究依据生物信息学分析,采用RT-PCR(Reverse transcription polymerase chain reaction)方法从棉花中克隆了一个b ZIP转录因子基因,命名为Ghb ZIP15(Gen Bank登录号为KP938299)。该基因c DNA全长1980 bp,其开放阅读框为966 bp,编码321个氨基酸的蛋白,预测分子量为37.1 k D,等电点为7.44。SMART蛋白结构预测发现,该蛋白含有b ZIP家族典型的BRLZ碱性结构域和亮氨酸拉链,属于B-zip1家族。系统进化树分析表明Ghb ZIP15属于b ZIP转录因子AREB亚家族,和拟南芥A亚家族的Atb ZIP12,At ABF1和At ABF2亲缘关系最近。洋葱表皮细胞中瞬时表达分析表明,Ghb ZIP15主要定位于细胞核中。RT-PCR分析表明Ghb ZIP15对干旱、高盐、低温等处理都有一定程度的响应,推测该基因对棉花非生物胁迫的调控起重要作用。

b ZIP transcription factors are important proteins involved in response to abiotic stresses in plants. In this study, a gene encoding b ZIP transcription factor was isolated in cotton using reverse transcription polymerase chain reaction（RT-PCR） according to bioinformatic analysis. The gene was named Ghb ZIP15（Gen Bank accession No. KP938299）. Sequence analysis showed that the full-length of Ghb ZIP15 gene was 1980 bp, containing a 966 bp open reading frame which encoded a protein of321 amino acids with predicted molecular weight of 37.1 k D and an isoelectric point of 7.44. SMART analysis showed that Ghb ZIP15 contains a typical BRLZ motif（basic region domain and leucine zipper domain） of the B-zip1 family. Phylogenetic analysis revealed that Ghb ZIP15 belonged to the AREB subfamily of the b ZIP family and was related closely to Atb ZIP12, At ABF1 and At ABF2. Ghb ZIP15 was localized inside the nuclei of transformed onion epidermal cells. RT-PCR analysis indicated that Ghb ZIP15 gene expression changed with different response to various abiotic stresses（dehydration, high salinity, and low temperature）, indicating that it may play important roles in the adaptation to abiotic stresses in cotton.