木薯氰苷合成关键酶基因MeCYP79D2的克隆及表达分析  

Cloning and Expression Analysis of Key Enzyme Gene MeCYP79D2 for Cyanoside Synthesis in Cassava

作　　者：肖鑫辉[1] 于晓玲[2] 张洁[1] 符乃方[1] 薛茂富[1] 韦卓文 叶剑秋[1] 王明[1] XIAO Xinhui;YU Xiaoling;ZHANG Jie;FU Naifang;XUE Maofu;WEI Zhuowen;YE Jianqiu;WANG Ming(Tropical Crops Genetic Resources Institute,Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Germ-plasm Resources Conservation and Utilization of Cassava,Ministry of Agriculture and Rural Affairs,Haikou,Hainan 571101,China;Institute of Tropical Bioscience and Biotechnology,Chinese Academy of Tropical Agricultural Sciences,Haikou,Hainan 571101,China)

机构地区：[1]中国热带农业科学院热带作物品种资源研究所/农业农村部木薯种质资源保护与利用重点实验室,海南海口571101 [2]中国热带农业科学院热带生物技术研究所,海南海口571101

出　　处：《热带作物学报》2024年第11期2258-2268,共11页Chinese Journal of Tropical Crops

基　　金：海南省自然科学基金青年基金项目(No.321QN318);中国热带农业科学院热带作物品种资源研究所非营利科研启动经费人才专项(No.PZS2023020);国家木薯产业技术体系项目(No.CARS-11-HNLKM)

摘　　要：氰苷含量是木薯改良的重要靶标性状,MeCYP79D2是木薯氰苷合成的限速酶基因之一。本研究以食用木薯品种SC9为材料,克隆木薯细胞色素P450酶家族中的MeCYP79D2基因,通过生物信息学软件对其进行分析,利用实时荧光定量PCR检测其在不同木薯种质块根中的表达特性,采用高效液相色谱仪测定氰化物的含量,并分析其与MeCYP79D2基因表达量的相关性。研究结果显示:MeCYP79D2基因编码区序列长度为1625 bp,编码528个氨基酸,属于不稳定脂溶性亲水蛋白,具有38个磷酸化位点;序列比对表明该基因保守性较高;系统进化分析显示MeCYP79D2与橡胶及麻风树关系较近;氰苷含量不同的木薯种质资源块根中MeCYP79D2基因表达量与氰苷含量存在极显著正相关;茉莉酸甲酯处理后,根中MeCYP79D2基因的表达显著上调且氰苷含量显著升高。本研究结果表明MeCYP79D2参与氰苷合成,为解析木薯氰苷生物合成的分子机制研究提供理论基础。The level of cyanogenic glucosides content is an important trait for the edible quality of cassava,and Me-CYP79D2 is one of the key enzyme genes regulating cassava cyanogenic glucosides synthesis.This study used the edi-ble variety SC9 as the material,cloned the MeCYP79D2 gene in the cytochrome P450 enzyme family of cassava,ana-lyzed it using bioinformatics software,and detected its expression characteristics in different cassava germplasm tubers using real-time quantitative PCR.The cyanogenic glucosides content was measured using HPLC,and its correlation with the expression level of MeCYP79D2 gene was analyzed.The results showed that the length of the coding region sequence of MeCYP79D2 gene was 1625 bp,encoding 528 amino acids.It belonged to an unstable lipophilic hydro-philic protein with 38 phosphorylation sites.Sequence alignment indicated that the gene was highly conserved,and phylogenetic analysis showed that MeCYP79D2 was closely related to rubber and leprosy trees.There was a significant positive correlation between the expression of MeCYPD2 gene and the content of cyanogen glycosides in cassava roots of germplasms with different levels of cyanogen glycosides.After treatment with methyl jasmonate,the expression of MeCYP79D2 gene in roots was significantly upregulated and the content of cyanogenic glucosides was significantly increased.The results of this study indicates that MeCYP79D2 is involved in cyanogenic glucosides synthesis,providing a theoretical basis for studying the molecular mechanism of cassava cyanogenic glucosides biosynthesis.

关 键 词：木薯 细胞色素P450单加氧酶 氰苷 基因克隆 

分 类 号：S533[农业科学—作物学]