花生HyPGIP基因克隆及抗叶腐病表达分析

Cloning and expression analysis of HyPGIP gene related to peanut leaf rot resistance

本文采用基因克隆和生物信息学方法研究了花生Hy PGIP基因及编码蛋白的基本性质和生物学功能,并通过测定接种叶腐病菌后花生植株内PG酶的活性变化和PGIP蛋白的生成量变化,以及Hy PGIP基因瞬时表达分析,探讨了PGIP蛋白与寄主抗病性关系。结果表明,受叶腐病菌侵染的花生植株中,抗病品种的PG酶活性都明显低于感病品种,而生成的PGIP蛋白量都比感病品种显著多,暗示PGIP蛋白与花生叶腐病抗性有关。经基因克隆和测序获得HyPGIP基因全长序列为1 029 bp,编码342个氨基酸,无内含子,终止密码子为TGA,与已报道的五个花生PGIP序列的同源性都很高;结构预测发现该序列存在8个LRR结构域,存在信号肽,疏水性较强,定位于细胞壁上;RT-PCR显示,经接种叶腐病菌处理后,花生植株中的PGIP基因表达量明显增加。

In this paper,the basic and biological functions of HyPGIP gene and its encoded protein were studied by gene cloning and bioinformatics methods,and the relationship between PGIP protein and host disease resistance was explored by determining PG enzyme activity,PGIP protein content and analyzing transient expression of HyPGIP gene in peanut plants after inoculation with Rhizoctonia solani. The results indicated that,PG activity in the resistant cultivars was significantly lower than that of in the susceptible cultivars,while the PGIP protein content in the resistant cultivars was significantly higher than that of in the susceptible cultivars,this result suggested that PGIP protein was related to peanut rot resistance. The full-length sequence of HyPGIP gene was 1 029 bp,encoding 342 amino acids,no intron,and the termination codon was TGA,which was highly homologous to the reported 5 PGIP sequences. There were 8 LRR domains in the sequence,and there were signal peptides,stronger hydrophobicity and located on the cell wall. RT-PCR showed that PGIP gene expression in peanut plants significantly increased after inoculation with R. solani.