金荞麦查尔酮合成酶基因CHS的克隆及序列分析

采用同源克隆的方法获得金荞麦查尔酮合成酶基因(CHS)的保守片段554bp,进一步采用染色体步移法(genome-walking)和RT-PCR技术克隆到CHS基因的全长DNA序列和cDNA开放阅读框(ORF)序列。序列分析结果表明,金荞麦CHS基因DNA全长1650bp,含一个462bp的内含子;其cDNA编码区全长1188bp,编码395个氨基酸,命名为FdCHS,NCBI登录号为GU169470。该氨基酸序列与同为蓼科的掌叶大黄、虎杖CHS的氨基酸序列同源率分别达到94%和93%,且含有CHS活性位点和底物结合口袋位点等保守位点。

Cloning and sequence analysis of the chalcone synthase gene (CHS) from Fagopyrum dibotrys

The conservative sequence of the chalcone synthase gene from Fagopyrum dibotrys 544 bp was isolated by homology cloning, and then the full-length DNA and cDNA ORF (open reading frame) sequences were cloned by genome-walking and RT-PCR, respectively. Sequence analysis showed that the CHS DNA of F. dibotrys was 1 650 bp, including one 462 bp intron. The coding region of cDNA was 1 188 bp, encoding 395 amino acids, designated as FdCHS and included the conserved sites of CHS such as active sites and substrate-binding pocket sites. The homology analysis of FdCHS with that of other plants showed that it was closely related to Rheum palmatum and Polygonum cuspidatum with 94% and 93% homology, respectively. The sequence accession number is GU169470 in GenBank.