油葵(Helianthus annuus)HaDGAT1基因的克隆与生物信息学分析

Cloning and Bioinformatics Analysis of HaDGAT1 Gene from Oil Sunflower (Helianthus annuus)

油葵(Helianthus annuus L.)种子富含不饱和脂肪酸,主要是亚油酸。亚油酸是人体必需的脂肪酸,能降低血液胆固醇,预防动脉粥样硬化,发挥抗癌作用。二酰基甘油酰基转移酶(diacylglycerol acyltrabsferase,DGAT)作为一种限速酶在油葵合成三酰甘油的过程中发挥重要作用。本研究通过对油葵种子转录组测序,利用PCR方法成功克隆得到一个DGAT1基因的c DNA序列,命名为HaDGAT1。对油葵HaDGAT1基因进行生物信息学分析,发现油葵HaDGAT1基因CDS全长1 440 bp,共编码479个氨基酸,所编码蛋白的分子量为55.740 kD,理论等电点为9.24。油葵Ha DGAT1为疏水性蛋白,亚细胞定位预测在内质网膜上。该蛋白的二级结构中α螺旋(44.05%),β转角(1.88%),延伸链(13.36%)和无规则卷曲(40.71%),与预测的蛋白质三级结构一致。本研究为进一步深入了解HaDGAT1基因的功能和调控机制和利用基因工程技术调节油葵脂肪酸的含量、改良油葵油的品质提供了理论依据。

Oil sunflower(Helianthus annuus L.) seeds are rich in unsaturated fatty acids, mainly linoleic acid.Linoleic acid is an essential fatty acid that can lower blood cholesterol, prevent atherosclerosis, and exert anti-cancer effects. Diacylglycerol acyltransferase(DGAT), as a rate-limiting enzyme, plays an important role in the synthesis of triacylglycerol from oil sunflower. In this study, the transcriptome of oil sunflower seeds were sequenced and the cDNA sequence of DGAT1 gene was successfully cloned by PCR, named as HaDGAT1. Bioinformatics analysis of Ha DGAT1 gene revealed that the gene CDS was 1 440 bp in length and encoded a protein of 479 amino acids with a predicted molecular weight of 55.740 kD, and theoretical isoelectric point of 9.24. It was a hydrophobic protein and the subcellular was localized in the endoplasmic reticulum membrane. In the secondary structure of the oil sunflower HaDGAT1 protein, helix(44.05%), β turn(1.88%), extended chain(13.36%) and random coil(40.71%) were consistent with the predicted protein tertiary structure. This study laid a foundation for further understanding of the function and regulatory mechanisms of HaDGAT1 gene. It provides a theoretical basis for improving the content of fatty acids in oil sunflower by using relevant genetic engineering techniques and improving the quality of oil sunflower.