香蕉八氢番茄红素合成酶基因MsPSY2a功能鉴定  

Functional Identification of Phytoene Synthase Gene MsPSY2a in Banana

作　　者：谢龙海 高洁 荆永琳 徐立[1,2] 陈莹 薛丙涛 李志英 Xie Longhai;Gao Jie;Jing Yonglin;Xu Li;Chen Ying;Xue Bingtao;Li Zhiying(Institute of Tropical Agriculture and Forestry,Hainan University,Haikou,570228;National Gene Bank of Tropical Crops,Key Laboratory of Tropical Crops,Germplasm Resources,Genetic Improvement and Innovation of Hainan Province,Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China of Ministry of Agriculture,Institute of Tropical Crops Genetic Resources,Chinese Academy of Tropical Agricultural Sciences,Danzhou,571700)

机构地区：[1]海南大学热带作物学院,海口570228 [2]中国热带农业科学院热带作物品种资源研究所,农业部华南热带作物基因资源与种质创制重点开放实验室,海南省热带作物种质资源遗传改良与创新重点实验室,国家热带作物中期库,儋州571700

出　　处：《分子植物育种》2021年第24期8071-8080,共10页Molecular Plant Breeding

基　　金：海南省重点研发计划项目(ZDYF2019214);中央级科研院所基本科研业务费专项(1630032019018,1630032019026)共同资助。

摘　　要：通过对香蕉转录组测序分析,筛选出类胡萝卜素途径相关基因MsPSY2a。本研究利用PCR方法从香蕉‘Karat’叶片中成功克隆出目的基因MsPSY2a的c DNA序列。MsPSY2a基因全长为1551 bp,开放阅读框(ORF)为1184 bp,编码394个氨基酸,是类胡萝卜素合成途径中的首要限速酶。Ms PSY2a蛋白具有PSY家族保守结构域PLN02632。RT-qPCR结果表明,MsPSY2a基因在香蕉根、茎、叶、果肉、果皮中表达量差异显著,大小依次为茎>果肉≈果皮>叶>根。本研究构建35S::MsPSY2a过表达载体,在拟南芥中过量表达,结果导致拟南芥种子由原来的黄褐色变化为浅黄褐色,且转基因拟南芥种子中积累的类胡萝卜素含量比野生型高18.75%,该结果表明MsPSY2a基因参与植物类胡萝卜素合成并具有正调控作用。本研究初步探索MsPSY2a基因的生物学功能,并为进一步探明香蕉类胡萝卜素合成途径分子机制和香蕉营养强化育种奠定一定基础。MsPSY2 a gene related to carotenoid biosynthetic pathway was screened out by sequencing analysis of banana transcriptome.The c DNA sequence of MsPSY2 a was cloned from’Karat’leaves by PCR,and the full length was 1551 bp.MsPSY2 a gene encoding 394 amino acids,which was the primary rate-limiting enzyme in carotenoid biosynthesis with an open reading frame of 1184 bp.MsPSY2 a protein has PSY familyconserved domain PLN02632.The RT-qPCR results showed that the expression of MsPSY2 a gene was significantly different in banana root,stem,leaf,pulp and peel.The expression level was stem>pulp≈peel>leaf>root.In this study,the35 S::MsPSY2 a overexpression vector was successfully constructed,and was transformed into Arabidopsis.As a result,Arabidopsis seeds changed from reddish brown to fawn,and carotenoid accumulation in transgenic Arabidopsis seeds was 18.75%higher than that in the wild type.The result indicated that MsPSY2 a gene is involved in carotenoid biosynthesis in plants and has positive regulation.This research provided preliminary study on the biological function of MsPSY2 a gene,and it was helpful for the further exploration of the molecular mechanism of banana carotenoid biosynthetic pathway and nutrition enhanced breeding of bananas.

关 键 词：香蕉 类胡萝卜素 八氢番茄红素合成酶 MsPSY2a 基因克隆 

分 类 号：S668.1[农业科学—果树学]