葡萄风信子MaGT1基因的克隆及其表达分析  

Cloning and Expression Analysis of MaGT1 Gene from Muscari ameniacum

作　　者：梁沛雯 娄倩 刘雅莉[1,2] LIANG Peiwen;LOU Qian;LIU Yali(College of Landscape Architecture and Arts,Northwest A&F University,Yangling,Shaanxi 712100,China;State Key Laboratory of Crop Stress Biology in Arid Areas,Ministry of Agriculture Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China,Northwest A&F University,Yangling,Shaanxi 712100,China;College of Horticulture,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学风景园林艺术学院,陕西杨陵712100 [2]西北农林科技大学旱区作物逆境生物学国家重点实验室,农业部西北地区园艺作物生物学与种质创制重点实验室,陕西杨陵712100 [3]西北农林科技大学园艺学院,陕西杨陵712100

出　　处：《西北植物学报》2019年第6期1001-1008,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(3147905);国家自然科学青年科学基金(31701962)

摘　　要：该研究以葡萄风信子(Muscari ameniacum)‘亚美尼亚’为试材,克隆了花青素合成途径过程中的类黄酮糖基转移酶基因MaGT1(GenBank登录号MK652470)。该基因开放阅读框全长1 338 bp,编码445个氨基酸,预测蛋白分子量为49.301 kD,理论等电点为5.40。结构分析显示,MaGT1蛋白具有PSPG保守结构域、UDP-糖基转移酶家族结构域和UDP-葡萄糖醛酸基/葡萄糖基转移酶保守域(UDPGT)。进化分析表明,MaGT1蛋白与油棕、海枣、葡萄亲缘关系相近,聚类于类黄酮糖苷糖基转移酶类分支,以UDP-葡萄糖/鼠李糖为主要糖供体。花青苷含量测定显示,花青苷仅在葡萄风信子着色的花中积累,在根、鳞茎和叶以及未着色的花蕾(S1)中几乎检测不到花青苷,且随着花的发育,花青苷含量不断增加,并在衰败期(S5)达到最高。荧光定量PCR分析表明,MaGT1基因的表达具有显著的时空特异性,并在花中优势表达,而在根、鳞茎和叶片中微量表达;在花发育不同阶段,MaGT1基因的表达量随着花发育不断增加,并在盛花期达到峰值。研究表明,MaGT1蛋白催化反应是花青素合成途径中的重要修饰步骤。该研究结果为进一步分析MaGT1基因在葡萄风信子花青素合成和调控中的功能提供了依据。In this study,a flavonoid glycosyltransferase gene in the anthocyanin synthesis pathway was isolated from petals of Muscari ameniacum and designated as MaGT 1(GenBank accession was MK652470).The full-length of ORF was 1 338 bp,encoding 445 amino acids.The molecular weight of the predicted enzyme was 49.301 kD and the pI value was 5.40.The results of structural analysis revealed that the deduced MaGT1 protein contains a typical conserved PSPG motif,an UDP-glycosyltransferase family domain and an UDP-glucuronosyltransferase/glucosyltransferase domain(UDPGT).The results of evolutionary analysis showed that MaGT1 protein is closely related to Elaeis guineensis,Phoenix dactylifera and Vitis vinifera and belongs to the flavonoid glycoside glycosyltransferase branch,with UDP-glucose/rhamnose as the main sugar donor.Anthocyanin content assay showed that anthocyanins only accumulate in the flowers of M.ameniacum,but almost no anthocyanins were accumulated in roots,bulbs and leaves,and uncolored flower buds(S1),and with the flower development process,the content of anthocyanins increased continuously and reached the highest in the decay period(S5).The results of real-time PCR showed that the expression of MaGT1 gene has significant space-time specificity.It is predominantly expressed in flower tissues and is rarely expressed in roots,bulbs and leaves.At different flower development stages,the expression level of MaGT1 gene increased with flower development and peaked at the fully opened petal stage.The results showed that the catalytic reaction of MaGT1 protein is an important modification step in the anthocyanin synthesis pathway.This study provides a basis for further study of the function of MaGT1 gene in the synthesis and regulation of anthocyanins in M.ameniacum.

关 键 词：葡萄风信子 葡糖基转移酶 基因克隆 表达分析 

分 类 号：Q785[生物学—分子生物学] Q786