膜荚黄芪查尔酮合成酶基因的克隆与表达分析

Cloning and expression analysis of CHS gene in Astragalus membranaceus

查尔酮合成酶( Chalcone synthase ,CHS)是生物合成黄酮类的关键酶和限速酶。该研究从膜荚黄芪中克隆了1个 CHS 基因,Genbank登陆号为KY086285( AmCHS )。 AmCHS 全长cDNA为1 473 bp,开放阅读框为1 170 bp,编码389个氨基酸,其分子量为42 828.51 Da,等电点为 6.05。生物信息学分析表明:AmCHS蛋白与其它植物 CHS 同源,无信号肽,定位于细胞质。实时荧光定量PCR和高效液相色谱分析结果显示:AmCHS在根、茎、叶中的表达水平与异黄酮的积累变化一致,证明了AmCHS 的表达与膜荚黄芪异黄酮的积累密切相关。

Chalcone reductase (CHS) is a key and rate-limiting enzyme in biosynthesis of flavonoids. A CHS gene was cloned from Astragalus membranaceus in the present study, the Genbank accession number was KY086285 ( AmCHS ), the full-length cDNA of AmCHS was 1 473 bp with 1 170 bp open reading frame, which encoding a protein comprised of 389 amino acids with the molecular weight of 42 828.51 Da and isoelectric point of 6.05. Bioinformatics analysis showed that AmCHS was homology with other plant CHS The results of Real-time PCR and HPLC analysis revealed that expression levels of AmCHS agreed with changes of isoflavone contents in different tissues. These results above indicated that the cloned AmCHS here was a novel CHS gene and the expression of AmCHS might be relevant to isoflavone accumulation in A. membranaceus.