大叶蛇葡萄无色花色素还原酶基因的克隆及其序列分析

Cloning and Bioinformatics Analysis of LAR Gene from Ampelopsis megalophylla

无色花色素还原酶(LAR)是植物类黄酮合成途径中一个关键酶。本研究根据大叶蛇葡萄转录组测序得到了无色花色素还原酶(LAR)基因序列,通过RT-PCR技术克隆得到LAR基因cDNA全长,并对该序列进行生物信息学分析。结果表明:大叶蛇葡萄LAR基因cDNA全长为1 267 bp,包含一个长度为1 170 bp的开放阅读框,编码389个氨基酸,理论蛋白分子质量为42.38 kD,等电点为7.73。氨基酸多序列比对发现,该序列与同科植物葡萄等具有较高的同源性。生物信息学分析表明LAR为亲水性蛋白,不含信号肽,很可能定位于细胞质。本研究为进一步研究LAR基因的功能,阐明该基因在大叶蛇葡萄类黄酮合成路径中的作用提供了新的线索。

The leucoanthocyanidin reductase is the key enzyme in the plant flavonoid biosynthetic pathway. We got the LAR gene sequence based on the transcriptome sequencing data of Ampelopsis megalophylla. Then the full-length of LAR gene was cloned by using RT-PCR technology and analyzed it by bioinformatic methods. The results indicated that the full-length of LAR gene in Ampelopsis megalophylla was 1 267 bp, containing a 1 170 bp open reading frame(ORF) which encoded 389 amino acids. The theoretical protein molecular weight was 42.38 kD and its isoelectric point was 7.73. The multiple alignments of its amino acids showed that LAR had high homology with Vitis vinifera. The bioinformatics analysis found that LAR was a hydrophilic protein and had no signal peptide, which was likely to locate in the cytoplasm. The study provided a new clue to further explore the function of LAR gene and illustrated the role of LAR gene in flavonoid biosynthetic pathway of A. Megalophylla.