刺芹侧耳两种保护酶基因的克隆、分析及温度对其表达量的影响

为了探究温度胁迫下刺芹侧耳中过氧化氢酶和铜锌超氧化物歧化酶基因的作用,本研究通过RT-PCR方法对刺芹侧耳转录组数据库检索得到的过氧化氢酶（CAT）和铜锌超氧化物歧化酶（Cu/Zn-SOD）基因进行克隆,并利用荧光定量PCR分析在高低温胁迫下CAT和Cu/Zn-SOD基因的表达量,以探讨刺芹侧耳中这两种保护酶基因在高、低温胁迫下的响应特征。结果表明,克隆得到的CAT和Cu/Zn-SOD基因开放阅读框长度分别为1 581bp和582bp,分别编码526个和193个氨基酸,分子量分别为59.6kDa、19.62kDa,等电点分别为6.35、6.31。在高温（35℃）和低温（4℃）两组处理中,CAT和Cu/Zn-SOD基因的表达量及酶活均在处理48h时达到最高且与对照组呈现显著差异,说明两种基因在刺芹侧耳抵御高低温胁迫的过程中具有重要作用。本研究结果初步研究了温度胁迫下刺芹侧耳中CAT与Cu/Zn-SOD基因的生物学功能,为进一步解析刺芹侧耳抵抗温度胁迫的机理奠定基础。

Cloning and analyses of two protective enzyme genes in Pleurotus eryngii and effects of temperature stress on their expression

The effects of catalase and copper-zinc superoxide dismutase genes in Pleurotus eryngii under temperature stress were investigated. The catalase (CAT) and copper-zinc superoxide dismutase (Cu/Zn-SOD) genes were cloned by RT-PCR and their expression levels under high and low temperature stress were analyzed by real-time PCR. The results showed that the open reading frames of CAT and Cu/Zn-SOD genes were 1 581bp and 582bp, encoding 526 and 193 amino acids, respectively. The molecular weight of amino acids were 59.6kDa and 19.62kDa and the isoelectric points were 6.35 and 6.31, respectively. Under high temperature (35°C) and low temperature (4°C) treatment, the expression levels and enzyme activities of CAT and Cu/Zn-SOD genes reached the highest in 48h and both of them showed significant difference in comparison with untreated group, indicating CAT and Cu/Zn-SOD genes played an important role in the process of resisting temperature stress.