柿果实采后软化中PG酶活性及其基因DkPG1的表达  

Effects of Propylene and 1-Methylcyclopropene on PG Activities and Expression of DkPG1 Gene During Persimmon Softening Process

作　　者：姜妮娜[1] 饶景萍[1] 付润山[1] 索江涛[1] 

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《园艺学报》2010年第9期1507-1512,共6页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(30771756);农业部西北园艺种质资源与遗传改良重点开放实验室项目

摘　　要：为了进一步探索多聚半乳糖醛酸酶(PG)在柿(Diospyros kaki L.)采后软化中的分子调控机制,应用实时荧光定量PCR技术和DNS比色法检测常温下丙烯和1-甲基环丙烯(1-MCP)处理‘富平尖柿'果实中PG基因DkPG1的表达量和PG酶活性的变化。结果显示,随着柿果实成熟软化,DkPG1基因转录水平呈先上升后下降的趋势,其中丙烯处理4d出现表达高峰,比对照提前12d且峰值极显著高于对照,而1-MCP处理的果实中的表达高峰出现在处理后28d,比对照推迟12d峰值极显著低于对照。丙烯处理果实PG酶活性迅速增加,活性峰与DkPG1表达高峰出现在同一天,1-MCP处理的果实PG酶活性明显降低,活性峰出现在DkPG1表达高峰前4d。此外,对不同处理下乙烯释放量和果胶组分变化分析的结果显示DkPG1基因的表达受乙烯调控,进而影响果胶组分代谢。In order to further explore the molecular regulation mechanism of PG during‘Fuping Jianshi＇persimmon（Diospyros kaki L.）postharvest softening with different treatments, and to improve the persimmon ripening and softening process,the responses of DkPG1 gene and PG activities in persimmon fruit to propylene and 1-MCP at the room temperature were investigated by real-time quantitative PCR （RT-qPCR）approach and DNS method.The results showed that accompanying with fruit ripening,the expressions of DkPG1 gene in fruits with different treatments had the same trend on the transcript level that it first steadily increased to the maximum and then decreased.After 4 days of propylene treatment,the expression of DkPG1 gene increased to the maximum which was dramatically higher than the control,and it appeared 12 days ahead of the control;The expression peak of DkPG1 gene in fruits treated with 1-MCP appeared at 28 days,12 days later than the control,which was significantly lower than the control.The activity of PG in fruits treated with propylene rapidly increased, and the activity peak appeared at the same day DkPG1 gene expression peak appeared;1-MCP treatment made the activity peak of PG decrease and appear 4 days earlier than its DkPG1 expression peak.Besides,the results about the analyze of ethylene release rate and pectin component showed the expressions of DkPG1 gene were regulated by ethylene,and then affected the pectin component metabolism.

关 键 词：柿 丙烯 1-甲基环丙烯 多聚半乳糖醛酸酶 实时荧光定量PCR 

分 类 号：S665.2[农业科学—果树学]