中国水仙NtMYB7基因的克隆及功能初步研究  

Cloning and Functional Characterization of NtMYB7 Gene in Narcissus tazetta var. chinensis

作　　者：王桂青 姚红 吴嘉诚 MUHAMMAD Anwar 曾黎辉[1] WANG Guiqing;YAO Hong;WU Jiacheng;MUHAMMAD Anwar;ZENG Lihui(College of Horticulture,Fujian Agriculture and Forestry University,Fuzhou 350002,China)

机构地区：[1]福建农林大学园艺学院,福州350002

出　　处：《西北植物学报》2018年第8期1401-1410,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：福建省自然科学基金(2016J01109);福建农林大学国际科技合作与交流项目(Kxb16013A)。

摘　　要：为研究中国水仙类黄酮代谢调控网络,从中国水仙(Narcissus tazetta var.chinensis)中克隆得到一个R2R3-MYB基因,命名为NtMYB7(GenBank登录号:MF522208)。序列分析表明,NtMYB7基因cDNA开放阅读框(ORF)为753bp,编码250个氨基酸。氨基酸多重序列比对分析发现,NtMYB7含有R2和R3保守结构域,属于R2R3-MYB家族;系统进化树分析结果显示,NtMYB7与花青素合成抑制因子聚为一类。实时荧光定量PCR分析发现,NtMYB7基因在中国水仙不同时期花瓣和副冠以及不同器官中均有表达,且NtMYB7基因在鳞茎盘中表达量最高。瞬时表达分析发现,NtMYB7使花青素合成激活因子StMYB诱导产生的红色变浅;定量PCR分析表明,NtMYB7基因显著抑制烟草黄酮醇代谢分支FLS基因的表达,同时抑制StMYB激活的花青素和原花青素合成结构基因的表达。研究结果初步判断,NtMYB7基因是中国水仙类黄酮代谢途径的抑制因子。In order to study the regulatory mechanisms of flavonoid metabolic pathway in Chinese narcissus,we cloned a R2R3-MYB gene named NtMYB 7(GenBank accession MF522208).The sequence analysis showed that NtMYB 7 had a 753 bp ORF,encoding 250 amino acids.Amino acid sequence analysis showed that NtMYB7 contained conserved R2 and R3 binding domains.NtMYB7 was grouped with anthocyanin repressors by phylogenetic tree analysis.The expression level of NtMYB 7 gene was varied in different organs and different developmental stages of Chinese narcissus and was the highest in basal plates,which was investigated by qRT-PCR.Transient expression analysis found NtMYB 7 reduced the red pigment induced by the anthocyanin synthesis activating factor StMYB.Quantitative PCR analysis showed that NtMYB 7 significantly repressed the expression of tobacco FLS gene which belongs to flavonoid metabolic branch.At the same time,NtMYB 7 down-regulated the expression of anthocyanin and proanthocyanidin synthesis structural genes activated by StMYB in tobacco leaves.The results preliminarily identify NtMYB 7 as a repressor of the flavonoid metabolic pathway in Chinese narcissus.

关 键 词：中国水仙 R2R3-MYB 类黄酮代谢 抑制因子 结构基因表达 

分 类 号：Q785[生物学—分子生物学] Q786