三色堇酪氨酸脱羧酶基因表达的位置效应  

Positional Effects of the Expression of Tyrosine Decarboxylase Gene in Pansy(Viola×wittrockiana)

作　　者：饶英 林颖 王健[2] 刘国锋 张文娥[1] 彭婷 RAO Ying;LIN Ying;WANG Jian;LIU Guofeng;ZHANG Wene;PENG Ting(College of Agriculture/Key Laboratory Plant Resources Conservation and Germplasm Innovation in Mountainous Region(Ministry of Education),Guizhou University,Guiyang,Guizhou 550025;Key Laboratory of Germplasm Resources Biology of Tropical Special Ornamental Plants of Hainan Province/College of Forestry,Hainan University,Haikou,Hainan 570228;Department of Botany,Guangzhou Institute of Forestry and Landscape Architecture,Guangzhou,Guangdong 510405)

机构地区：[1]贵州大学农学院/山地植物资源保护与种质创新教育部重点实验室,贵州贵阳550025 [2]海南省热带特色花木资源生物学重点实验室/海南大学林学院,海南海口570228 [3]广州市林业和园林科学研究院,广东广州510405

出　　处：《核农学报》2023年第9期1720-1728,共9页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金(32060365);贵州省科技计划项目(黔科合基础-ZK[2022]一般095);贵州省科技计划项目(黔科合[2018]2302);贵州大学引进人才科研项目([2016]-45)。

摘　　要：植物酪氨酸脱羧酶(TyDC)被认为在花色素形成过程中起作用。三色堇有丰富的花斑变异。为探究酪氨酸脱羧酶基因与花色素形成之间的关系,本研究从三色堇(Viola×wittrockiana)克隆到一个新的酪氨酸脱羧酶基因,命名为VwTyDC-like,并分析了其基因结构、序列特征、系统进化和时空表达模式。结果显示,VwTyDC-like基因gDNA序列为2007 bp,包含2个外显子和1个内含子,编码序列(CDS)为1497 bp,编码498个氨基酸,分子量为54.94 kDa。系统进化树分析显示,VwTyDC-like与VwTyDC蛋白亲缘关系最近。实时荧光定量PCR(qRT-PCR)分析结果表明,VwTyDC-like和VwTyDC基因在不同组织器官、花发育的不同时期、唇瓣不同区域和不同花色品种中的表达模式高度一致,但VwTyDC-like基因的表达量普遍高于VwTyDC。VwTyDC-like和VwTyDC基因在花中的表达量最高;在花发育的S7期,2个基因在花瓣基部的中心色斑区的表达量显著高于非色斑区。在三色堇不同花色品种中,无论花瓣是否带花斑,VwTyDC-like和VwTyDC基因在中心色斑区或其对应区的表达量均显著高于非色斑区或其对应区。同时,在有斑及无斑品种唇瓣的不同区域,2个基因的表达量均由花瓣基部向外逐渐递减。由此推测,VwTyDC-like和VwTyDC在花瓣中的表达具有明显的位置效应。本研究为三色堇花色育种及TyDC基因的功能研究提供了候选基因资源和理论基础。Tyrosine decarboxylase(TyDC)is supposed to play an important role in the formation of flower colors.Pansy(Viola×wittrockiana)has plentiful variations in flower blotch areas.To investigate the relationship between pansy TyDC and the formation of flower colors,a new gene encoding tyrosine decarboxylase was cloned from pansies,named VwTyDC-like.The gene structure,sequence characteristics,phylogenetic relationship and expression patterns of VwTyDC-like were analyzed in this study.The results showed the gDNA sequence of VwTyDC-like is 2007 bp in length,containing 2 exons and 1 intron,and the coding sequence is 1497 bp in length,encoding a protein with 498 amino acids.The molecular weight of predicted protein is 54.94 kDa.Phylogenetic analysis indicated that VwTyDC-like is the closest to VwTyDC.qRT-PCR analyses indicated the expression patterns of VwTyDC-like and VwTyDC were highly consistent in different tissues,different stages of flower development,different areas of labellum and different flower colors,but the expression level of VwTyDC-like was generally higher than that of VwTyDC.Both VwTyDC-like and VwTyDC had the highest expression levels in pansy flowers.The expression levels of VwTyDC-like and VwTyDC in the central blotch areas were significantly higher than non-blotch areas at S7 of flower development.In pansy cultivars with different flower colors,regardless of petals with or without flower blotches,the expression levels of these two genes in the central blotches/their corresponding areas were obviously higher than in non-blotches/their corresponding areas.Meanwhile,in different regions of the labellum in both blotch and non-blotch cultivars,the expression of both VwTyDC-like and VwTyDC decreased gradually from the proximal of petals to the outward.Therefore,we speculate that the expression of VwTyDC-like and VwTyDC in pansy petals exhibits obvious positional effects.This study provided candidate genes and theoretical basis for pansy color breeding and TyDC gene function research.

关 键 词：三色堇 酪氨酸脱羧酶 表达模式 位置效应 色斑 

分 类 号：S682.19[农业科学—观赏园艺]