甘蔗谷胱甘肽硫转移酶基因SoGST-1a的克隆与表达分析

Cloning and Expression Analysis of Glutathione S-transferase Gene SoGST-1a in Sugarcane

克隆甘蔗谷胱甘肽硫转移酶(Glutathione S-transferase,GST)基因,并分析其序列特征和表达谱,为甘蔗抗旱育种提供基因来源。本研究采用电子克隆和RT-PCR技术从甘蔗品种‘新台糖22号’中克隆到一个甘蔗GST基因,命名为SoGST-1a。通过生物信息学软件分析其序列特征,采用实时荧光定量PCR检测其表达谱。序列分析表明该基因cDNA全长702 bp,编码224个氨基酸,预测的蛋白分子式为C1117H1750N300O328S6,蛋白分子量为24.82 k Da,等电点为5.96。蛋白疏水性分析推测其为亲水性蛋白。保守结构域预测表明SoGST-1a蛋白具有2个GST结构域。系统进化树分析表明该基因与玉米Zeta类GST蛋白亲缘关系最近。荧光定量PCR分析显示,干旱胁迫下SoGST-1a基因下调表达。研究结果表明,SoGST-1a基因可能在甘蔗干旱胁迫中并不发挥一定作用。这些结果为深入了解SoGST-1a基因的生物学功能奠定了基础。

The glutathione S-transferase（GST） gene from sugarcane was cloned. Its sequence characteristics and expression patterns were analyzed. This provided the source of gene in sugarcane breeding for droughtresistance. In this study, a GST gene from sugarcane variety ROC22 was cloned by in silico cloning and RT-PCR, named SoGST-1a. Its sequence characteristics were analyzed by using bioinformatics software, and itsexpression patterns were detected by using real-time PCR. Sequence analysis showed that the full lengthc DNA of SoGST-1a was 702 bp, which encoded 224 amino acids. The predicted protein molecular formula was C1117H1750N300O328S6, whose molecular mass was 24.82 k Da and isoelectric point was 5.96. Hydrophobic analysisindicated that it was a hydrophilic protein. Conserved domain prediction showed that SoGST-1a proteinhad two GST domains. Phylogenetic analysis showed that SoGST-1a protein was close to Zeta class GSTprotein of maize. Real-time PCR results showed that the So GST-1a gene was down-regulated expressionunder drought treatment. The research results showed that SoGST-1a gene might not play a role in droughtstress in sugarcane. These results provided a basis for further understanding biological function of So GST-1a.