桃PpSGR基因功能鉴定及其对乙烯合成的调控  

Function identification of PpSGR gene and its regulation of ethylene syn-thesis in peach

作　　者：邵允 张蒙蒙 陈云 王晓菲 董康 刘宁 张郎郎 谭彬[1] 王伟 程钧 冯建灿[1] SHAO Yun;ZHANG Mengmeng;CHEN Yun;WANG Xiaofei;DONG Kang;LIU Ning;ZHANG Lang-ang;TAN Bin;WANG Wei;CHENG Jun;FENG Jiancan(College of Horticulture,Henan Agricultural University,Zhengzhou 450002,Henan,China)

机构地区：[1]河南农业大学园艺学院,郑州450002

出　　处：《果树学报》2023年第12期2513-2523,共11页Journal of Fruit Science

基　　金：河南省杰出外籍科学家工作室(GZS2020007);国家河南省联合项目(U1804114)。

摘　　要：【目的】乙烯合成及果肉褪绿是桃果实成熟过程中相伴出现的两个生理事件。STAY-GREEN(SGR)是参与植物叶片和果实褪绿的重要基因。然而,桃SGR基因在果实成熟及褪绿过程中的功能尚不清晰,旨在初步探究PpSGR基因在桃果实成熟及褪绿过程中的功能。【方法】以秋蜜红为试验材料,对PpSGR基因进行克隆,对PpSGR的核苷酸及氨基酸序列进行分析,对不同发育时期桃果肉中PpSGR的转录水平进行检测,并对PpSGR基因调控叶绿素降解及乙烯合成的功能进行研究。【结果】PpSGR编码区全长为831 bp;该基因编码的蛋白序列含有1个高度保守的SGR域。PpSGR基因的表达水平随着果肉逐渐褪绿呈现上升的趋势。瞬时过表达PpSGR基因后,桃叶片颜色明显褪绿,并且在300 mmol·L-1NaCl的盐胁迫下,过表达PpSGR的叶片褪绿更加明显。此外,过表达PpSGR后,桃苗乙烯合成的限速基因PpACS1、PpACS4及PpACS6均表达上调,且内源乙烯释放量显著增多。【结论】对PpSGR的基因功能进行鉴定和研究,并分析了其对乙烯的调控作用,为进一步解析桃果实成熟及果肉褪绿提供了新的思路,也为不同成熟期桃品种的选育提供了理论基础。【Objective】Ethylene synthesis and disappearance of peel green color are two physiological events associated with fruit ripening of peach.STAY-GREEN(SGR)is a crucial gene that promotes dis-appearance of leaf and fruit green color in the plant kingdom.In various plant species,SGR genes exhib-it similar functions in regulating chlorophyll.Peach(Prunus persica)is a significant fruit globally.How-ever,the function of the PpSGR gene in the peach genome has not been identified,and its potential im-pact on green color disappearance and ripening of peach fruit remains unclear.This study aims to identi-fy the SGR gene in the peach genome,analyze the expression level of the PpSGR gene in different fruit maturity stages,and preliminarily investigate the function of the PpSGR gene.【Methods】The nucleo-tide sequences of the PpSGR gene were cloned from the Qiumihong cultivar.Bioinformatics analysis was conducted to analyze the gene structure of PpSGR in peach,the secondary and tertiary structure of the PpSGR protein was predict,the amino acid sequences of SGR in different species were compared,and a phylogenetic tree was constructed.Subsequently,the transcriptional level of the PpSGR gene in peach fruits at different maturity stages was analyzed using Quantitative Real-time PCR(qRT-PCR).The function of the PpSGR gene in chlorophyll degradation was preliminarily verified by transient over-expression in peach seedlings.Numerous studies have reported that the SGR gene can promote chloro-phyll degradation under salt stress,leading to leaf yellowing.To verify the function of SGR under salt stress,the Fv/Fm values were measured and analyzed using a chlorophyll fluorescence analyzer after dark treatment of the whole peach seedlings transiently infected with the PpSGR gene.Additionally,there is evidence suggesting that ethylene can promote the expression of the SGR gene,but whether the SGR gene has a direct effect on ethylene synthesis remains to be studied.Therefore,we measured ethyl-ene production and the transcriptional level

关 键 词：桃 STAY-GREEN(SGR) 褪绿基因 叶绿素降解 乙烯 

分 类 号：S662.1[农业科学—果树学]