特色油料作物油莎豆CeDGAT1基因的鉴定及表达分析  

Identification and Expression Analysis of CeDGAT1 Gene in Cyperus esculentus with a Special Oil Crop

作　　者：高宇[1] 陈莹 孙岩[1] 王晓清 高慧玲 薛金爱[1] 李润植[1] GAO Yu;CHEN Ying;SUN Yan;WANG Xiaoqing;GAO Huiling;XUE Jin'ai;LI Runzhi(Institute of Molecular Agriculture and Bioenergy,Shanxi Agricultural University,Taigu 030801,China)

机构地区：[1]山西农业大学分子农业与生物能源研究所,山西太谷030801

出　　处：《山西农业科学》2020年第6期831-835,841,共6页Journal of Shanxi Agricultural Sciences

基　　金：国家自然科学基因项目(31401430);国家“948”项目(2014-Z39);山西省煤基重点科技攻关项目(FT-2014-01);山西省重点科技项目(201603D312005);山西省回国留学人员科研资助项目(2015-064)。

摘　　要：二酰甘油酰基转移酶1(DGAT1)是催化三酰甘油酯(TAG)合成最后一步反应的限速酶,对油料作物种子油脂合成和积累极为重要。油莎豆地下块茎能积累30%的油脂,其块茎油脂生物合成机制还未解析。分析油莎豆块茎转录组数据,结果发现一条编码DGAT1的cDNA序列(CeDGAT1),并应用生物信息学工具解析了CeDGAT1酶蛋白的理化性质、高级结构及系统发育等特征,通过qRT-PCR检测CeDGAT1的时空表达谱。结果显示,CeDGAT1编码的蛋白长度为502个氨基酸,理论等电点为9.08,属于MBOAT蛋白超家族,是一个疏水性蛋白,含有8个跨膜结构;二级结构由α-螺旋(46.06%)、无规则卷曲(35.43%)、延伸链(12.40%)和β-折叠(6.10%)组成;油莎豆CeDGAT1蛋白与模式植物拟南芥AtDGAT1的亲缘关系较远,而与禾本科的单子叶植物高粱和野生水稻的DGAT1同源性较高;CeDGAT1主要在发育块茎中高表达,在块茎播种后90 d时达峰值,表明CeDGAT1在油莎豆块茎油脂合成积累中行使重要功能。研究结果可为深入解析块茎等营养器官油脂生物合成机制及油莎豆油脂产量和品质的遗传改良提供科学依据。Diacylglycerol acyltransferase 1(DGAT1)is a rate-limiting enzyme that catalyzes the final reaction of triacylglycerol(TAG)synthesis,and it is extremely important for oil biosynthesis and accumulation of oil crop seeds.The underground tuber of Cyperus esculentus can accumulate 30%of the oil,but it is not analyzed about oil biosynthesis mechanism of tuber.The CDs sequence of CeDGAT1 is derived from the transcriptome data determined by our laboratory.Bioinformatics tools were used to analyze the physicochemical properties,protein structure and phylogenetic characteristics of CeDGAT1 enzyme.qRT-PCR was used to detect CeDGAT1 spatiotemporal expression pattern.The results showed that CeDGAT1 protein encoded 502 amino acids,a theoretical isoelectric point of 9.08.The protein belonged to the MBOAT superfamily and was a hydrophobic protein with 8 transmembrane structures.The secondary structure was composed ofα-helix(46.06%),random coils(35.43%),extended chains(12.40%),andβ-sheets(6.10%).The CeDGAT1 protein did not seem to have high homology with Arabidopsis thaliana orthologs,but had a higher homology with DGAT1 of Poaceae plants Sorghum bicolor and Oryza brachyantha.CeDGAT1 mainly had a high expression in developing tubers,and reached the maximum at 90 d of tuber sowing.It showed that CeDGAT1 played an important role in the accumulation of oil in tubers of Cyperus esculentus.The study results will provide a scientific basis for in-depth analysis of the oil biosynthesis mechanism of tuber and other vegetative organs,provide a scientific basis for genetic improvement of oil yield and quality in Cyperus esculentus.

关 键 词：油莎豆 富油块茎 油脂合成 二酰甘油酰基转移酶1(DGAT1) 生物信息学分析 基因表达 

分 类 号：S565.9[农业科学—作物学]