苦荞类异黄酮还原酶基因(FtIRL)的克隆及序列分析

利用RT-PCR技术，从苦荞(Fagopyrum tatarium)中克隆得到类异黄酮还原酶基因(IRL)的开放阅读框序列(ORF)，命名为FtIRL。序列分析表明：FtIRL含一个长942bp的ORF，编码313个氨基酸，其氨基酸序列与金荞异黄酮还原酶FcIFR (GenBank登录号ABV02071)同源性最高，达到97%；与其他植物IRL同源性为44%～73%。生物信息学分析表明：FtIRL推导的蛋白质含有典型的底物结合口袋和保守的NADPH结合位点，符合短链脱氢酶家族的结构特征。构建基于氨基酸的系统发育树表明，苦荞FcIFR虽然在氨基酸序列上与其他植物的异黄酮还原酶(IFR)有较高的同源性，但其生物学功能可能更接近落叶松脂醇还原酶(PLR)。

Cloning and Sequence Analysis of the Isoflavone Reductase-like(FtIRL) Gene from Fagopyrum tatarium

The cDNA sequence of isoflavone reductase-like gene IRL from Fagopyrum tataricum was amplified by RT-PCR. Sequencing showed that the ORF of IRL gene from F. tataricum (named as FtIRL) was 942bp, probably encoding a protein of 313 amino acids. Further analysis indicated that the deduced FcIFR protein had homology values of 97% with other plants, IRLs. FtIRL possessed two short-chain dehydrogenase/reductase conserved motifs: a substrate-binding pocket and a NADPH binding site. The phylogenetic tree constructed based on amino acid sequences indicated that, although the amino acid sequence of IRL gene from F. tataricum had high homology with that of isoflavone reductase (IFR) genes from other plants, its biological function might be more similar to that of pinoresinol lariciresinol reductase (PLR).