罗汉果乙烯合成关键酶基因SgACS3的克隆及表达分析  

Cloning and Expression Analysis of ACC Synthase Gene(SgACS3) from Siraitia grosvenorii

作　　者：曾娜霞 胡姗姗[1] 郝庆林 辛佳佳 周琼[1] 李刚[2] ZENG Na-Xia;HU Shan-Shan;HAO Qin-Lin;XIN Jia-Jia;ZHOU Qiong;LI Gang(College of Agricultural, Guangxi University, Nanning 530004, China;Guangxi Botanical Garden of Medicinal Plant, Guangxi Key Laboratory of Medicinal Resources Protection and Genetic Improvement, Nanning 530023, China)

机构地区：[1]广西大学农学院,广西南宁530004 [2]广西药用植物园广西药用资源保护与遗传改良重点实验室,广西南宁530023

出　　处：《农业生物技术学报》2018年第5期784-792,共9页Journal of Agricultural Biotechnology

基　　金：国家自然科学基金项目(No.31260359);广西农业重点科技计划项目(No.201609)

摘　　要：罗汉果(Siraitia Grosvenorii)主要生长于广西北部,是一种以果实为重要收获对象的药食两用雌雄异株经济植物。为探讨乙烯信号途径在其性别形成中分子机制,基于罗汉果转录组unigene信息,结合cDNA末端快速扩增(rapid amplification of cDNA ends,RACE)技术和高效交错式热不对称聚合酶链式反应(high-efficiency thermal asymmetric interlaced polymerase chain reaction,hi-TAIL PCR)技术,分别从罗汉果总RNA和总DNA中克隆获得乙烯合成关键酶基因—1-氨基环丙烷-1-羧酸合成酶(1-aminocyclopropane-1-carboxylic acid synthase,ACS)ACS3的mRNA和DNA全长;通过qRT-PCR检测其在罗汉果雄株、雌株和Ag^+处理后的雌株不同时期不同组织部位中的相对表达量。结果表明,克隆得到的mRNA全长为1 954 bp,命名为SgACS3(GenBank登录号:KY705404),该基因全长DNA为2 530 bp,含有3个内含子;qRT-PCR结果表明,SgACS3基因在授粉前雌株叶和花芽中的表达尤为显著,且在Ag^+处理前的雌株的花芽和叶中的相对表达量均显著高于Ag^+处理后的雌株(P<0.05),表明SgACS3基因广泛参与罗汉果生长发育调节,与雌花芽分化、蕾中雄蕊发育,及其雌花的形成密切相关,并受Ag^+影响负调控表达。本研究为深入揭示SgACS3在调控罗汉果性别表达和花器官形态建成的中分子遗传机制和育种利用提供了基础。Siraitia Grosvenorii is an dioecious plant with medicinal and editable fruits as harvest, native to north of Guangxi Province, China. To explore the molecular mechanism of ethylene signal pathway, based on the unigene information from transcriptome data and combined with the rapid amplification of cDNA ends （RACE） technique and high-efficiency thermal asymmetric interlaced polymerase chain reaction （hi-TAIL PCR） technique, the full length mRNA and DNA of the key enzyme of ethylene synthesis was obtained from S. grosvenorii. The relative expression of genes on the male plant, female and Ag＋treated female plants at different stages of different tissue parts were detected by real-time fluorescence quantitative technique. The results showed that the total length of the mRNA was 1 954 bp, named as SgACS3 （GenBank accession number： KY705404）, and the full length DNA of the gene was 2 530 bp and contains three introns. The expressions of SgACS3 gene of the female leaves and buds before pollination were particularly high. The relative expressions of buds and leaves in the female plants were significantly higher than those in Ag＋treated plants, suggesting that SgACS3 gene was widely involved in the growth and development of S. grosvenorii, stamen development in the buds, and it was closely related to the formation of female flowers and Ag＋ by impact negatively regulate expression. This study provides an important base for revealing the molecular mechanism of SgACS3 in regulating the sex express and organ morphogenesis of flower and its application in breeding.

关 键 词：罗汉果  乙烯  RACE  hi-TAIL PCR  花芽分化 

分 类 号：S567.239[农业科学—中草药栽培]