毛竹β-1,4-糖苷酶基因cDNA克隆与表达分析

cDNA Cloning and Expression Analysis of Phyllostachys edulis Beta-1,4-Glycosidase Gene

根据水稻β-1,4-糖苷酶(korrigan)基因的保守区序列设计引物,以毛竹cDNA为模板,采用PCR方法,成功扩增出1个含有完整阅读框架的cDNA序列,长度为2191bp,共编码617个氨基酸,将其命名为PeKOR基因。其氨基酸序列分析的结果表明,PeKOR与其他β-1,4-糖苷酶有较高的同源性,同水稻序列相似性高达91%,且其序列具有典型的Glycosyl hydrolase9super family结构域,推测此PeKOR为毛竹β-1,4-糖苷酶基因。在竹笋中采用半定量方法研究该基因的表达情况,结果表明该基因在高温条件下表达量较低温条件下明显升高。

A beta-1,4-glycosidase protein gene from phyUostachys edulis,named as PeKOR,was cloned through PCR using primers designed according to the beta-1,4-glycosidase protein genes conserved region of other plant. The coding region of the genomic clone of PeKOR is continuous. The cDNA of PeKORcontains an open reading frame of 2 191 bp and codes for a protein of 617 aa. The database search using the amino acid sequence as query showed high homology to several beta-1,4-glycosidase proteins,especially the PeKOR sequence showed the maximum homology （91% identity）to Oryza sativa subspecies beta-1,4-glycosidase protein gene） , and it has a typically conserved domain of Glycosyl hydrolase 9 super family. Therefore we predicted that the PeKOR could be an beta-1,4-glyeosidase genein bamboo. The result of semiquantitative RT-PCR in bamboo shoots showed that expression of PeKOR gene was regulated by temperature, and the expression level on high temperature is larger than the one on low temperature.