甘蔗小分子量热激蛋白(sHSP)基因克隆及水分胁迫下的表达分析

Cloning of Small Heat-shock Protein(HSP)Gene from Sugarcane and Analysis of Its Expression Under Drought Stress

为甘蔗抗逆胁迫机制研究提供依据,以甘蔗叶片总RNA为模板,通过RT-PCR扩甘蔗小分子量热激蛋白(sHSP)基因的cDNA,采用生物信息学软件分析所克隆基因的编码蛋白特性,并用荧光定量PCR分析该基因的表达情况。结果表明,克隆得到的c DNA片段长度为659 bp,包括1个459 bp的开放阅读框,编码132个氨基酸。同源性分析表明,sHSP基因在14个不同植物中的一致性为69%-96%。甘蔗sHSP具有典型的HSP结构域,并且非常保守。实时荧光定量分析结果表明,随着甘蔗干旱胁迫时间的延长,sHSP基因表达量缓慢下降后明显增加,干旱胁迫加硅处理的甘蔗叶片sHSP基因表达量峰值出现比干旱处理推迟48 h。说明sHSP受到了干旱胁迫的诱导表达,同时硅能提高甘蔗抗旱性。

The present experiment was conducted to clone Small Heat-shock Protein（sHSP）in sugarcane to explore mechanism of stress resistance in sugarcane. sHSP was amplified using RT-PCR from sugarcane leaves,the characteristics of the deduced protein were analyzed using bioinformatics software and its expression was analyzed using quantitative real-time PCR. The results showed that the cDNA of HSP gene was 659 bp in full length with a 459 bp open reading frame,and encodes a putative sHSP protein with 152 amino acids. Comparison of the amino acids sequences homology in sHSP protein from 14 different species indicated that,the sHSP protein had 69% to 96% identity in amino acids sequence with other plants. The deduced amino acids sequence not only contained a typical sHSP domain,but also was conservative. The results of quantitative real-time PCR analysis showed that the m RNA of sHSP was decreased initially and then increased with time under drought stress. These results suggested that sHSP might be involved in function of water stress and drought resistance in sugarcane enhanced by Si application.