柑橘突变体青瓯柑果实采后滞绿的机理研究

项目名称： 柑橘突变体青瓯柑果实采后滞绿的机理研究

项目编号： No.31271968

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 农业科学

项目作者： 程运江

作者单位： 华中农业大学

项目金额： 88万元

中文摘要： 滞绿突变体是研究成熟果实叶绿素降解和衰老调控机理的珍贵资源。青瓯柑是瓯柑的芽变，是迄今极少数具有重要经济价值的柑橘滞绿突变体，成熟及贮藏期间果皮均不转色。过去三年的研究表明，青瓯柑果实贮藏性能明显优于普通瓯柑，而且无法用外源乙烯对其脱绿，成熟果实黄皮层总叶绿素、叶绿素a、叶绿素b、叶绿素酯a、脱镁叶绿甲酯酸a等成分均极显著高于普通瓯柑，这些组分均位于叶绿素降解关键酶脱镁叶绿甲酯酸a加氧酶（PAO）的上游，推测该酶与青瓯柑滞绿有关。表达谱芯片分析发现，外源乙烯处理后与叶绿素代谢相关的酶中仅有PAO基因显著差异表达，表明PAO是青瓯柑果皮叶绿素代谢途径中响应乙烯信号的关键基因之一。本项目拟在前期研究基础上，结合生物信息学分析，从基因结构与功能、上游调控元件、基因表达模式及蛋白修饰等水平解析PAO对青瓯柑果皮滞绿及对外源乙烯不敏感的机理。本研究对指导柑橘贮藏保鲜具有重要的理论及实践意义。

中文关键词： 果实色泽形成；转录组；转录调控；ABA；

英文摘要： Staygreen mutants are important resources to investigate the mechanisms of chlorophyll degredation and senescences of mature fruit.Qingougan mandarin (Citrus suavissima Tanaka),a bud mutant of Ougan mandarine (Citrus suavissima Tanaka), is a rare economiclly important staygreen mutant in citrus family,which fruit flavedo remains green colour throught the ripening and storage phases.Preliminary results from the studies in the past three years demonstrated that Qingougan showed better storability than that of wild type Ourgan, moreover, Qingougan can not be degreened by exogenous ethylene, and the contents of total chlorophyll, chlorophyll a, chlorophyll b, chlorophyllide a, and pheophorbide a are remarkably higher than that in the wild type Ougan. All the accumulated components located at the upstream of pheophorbide a oxygenase (PAO) in high plant chlorophyll metabolic pathway,which indicated that PAO played an important role in this staygreen phenotype. When mature Qingougan fruit were treated by exogenous ethylene, and the expression profile was detected by Affymetrix GeneChip Citrus Genome Arrays (Affymetrix, Santa Clara, CA, USA), only PAO gene among the genes of chlorophyll metobolic pathway was differentially expressed, which demonstrated that PAO was one of the core genes in chlorophyll degredation and s

英文关键词： Fruit Color formation；Transcriptome；Trancriptianal Regulation；ABA；