蓝莓不同硬度果实VcPLs基因克隆和功能研究  

Gene cloning and function analysis of VcPLs genes in blueberries with different fruit firmness

作　　者：李晓谊 陆晓莹 黄巧玉 李永强[1,2] 宗宇 徐丽珊[1,2] 郭卫东 LI Xiaoyi;LU Xiaoying;HUANG Qiaoyu;LI Yongqiang;ZONG Yu;XU Lishan;GUO Wei-dong(College of Life Sciences,Zhejiang Normal University,Jinhua 321004,Zhejiang,China;Zhejiang Provincial Key Laboratory of Bio-technology on Specialty Economic Plants,Zhejiang Normal University,Jinhua 321004,Zhejiang,China)

机构地区：[1]浙江师范大学生命科学学院,浙江金华321004 [2]浙江省特色经济植物生物技术重点实验室,浙江金华321004

出　　处：《果树学报》2024年第1期1-11,共11页Journal of Fruit Science

基　　金：浙江省农业新品种选育重大科技专项(2021C02066-9);浙江省科技厅重点研发计划项目(2018C02007);浙江省大学生科技创新活动计划暨新苗人才计划(2021R404079)。

摘　　要：【目的】探究果胶裂解酶基因在蓝莓硬肉品种和软肉品种果实硬度差异中的作用,为选育高硬度蓝莓品种提供参考。【方法】以蓝莓硬肉品种Star和软肉品种O’Neal不同发育时期的果实为材料,测定果实硬度、细胞壁物质含量和果胶裂解酶活力,分析比较果肉细胞解剖结构,克隆果胶裂解酶基因并研究其表达模式,转化番茄验证VcPL的功能。【结果】S4(膨大期)到S6(红果期)时期是果实硬度快速下降关键时期,果肉细胞在发育初期细胞壁轮廓清晰,Star果肉细胞出现结构破损的时期晚于O’Neal,果实硬度与可溶性果胶含量、果胶裂解酶活力均呈极显著负相关,VcPL41和VcPL65编码区序列长度分别为1230 bp和1209 bp,Star和O’Neal中VcPL65氨基酸序列完全相同,VcPL41的序列在品种间有4个氨基酸差异。2个基因在Star中快速上调表达的时期晚于O’Neal。超表达VcPL41和VcPL65的番茄果实硬度显著小于对照组,可溶性果胶含量显著高于对照组。【结论】蓝莓硬肉品种Star和软肉品种O’Neal果实硬度差异受果胶裂解酶活力和可溶性果胶含量影响,VcPL41和VcPL65能够加速果实成熟软化进程。【Objective】Fruit firmness is an significant classification indicator of fruit quality,which directly affects fruit mechanical harvesting,transportability,storage and processing.This study aimed to explore the function of the pectin lyase genes on fruit firmness between firm-flesh and soft-flesh blueberry cultivars in order to enrich the molecular mechanism of fruit firmness alteration,and to provide a reference for breeding high-firmness blueberry cultivars.【Methods】The blueberry fruits at six developmental stages from S3(fruit setting)to S8(maturation)of firm-flesh cultivar Star and soft-flesh cultivar O’Neal were used as materials for the study.The fruit firmness,cell wall components including cellulose,hemicellulose and soluble pectin were measured.The activity of pectin lyase were analyzed and the correlation between the fruit firmness and physiological and biochemical indicators were calculated.The fruit anatomical structures at six developmental stages were compared between two cultivars with firm and soft flesh.We screened two pectin lyase(PL)genes according to transcript abundance in the fruits at these six stages.The two PL genes were cloned and their expression patterns at six stages were studied using quantification PCR.The functions of VcPLs genes were checked through inducing overexpression in the tomato fruits.【Results】The fruit firmness of the two blueberry cultivars showed a downward trend as fruit development.They decreased rapidly from S4 to S6 stages,and then showed a gentle decrease trend.Both Star and O’Neal reached the maximum value of fruit firmness at the S4 stage.The critical stage for rapid decline of the fruit firmness happened from stages S4 to S6.At the early stages of the fruit development(S3 and S4),the flesh cells closed to the fruit skin were intact and tightly arranged without structure collapse.The boundary of the flesh cells was clear.The flesh cell structures of O’Neal and Star gradually became disordered as the fruit expansion.But the changes occured earlier

关 键 词：蓝莓 果实硬度 果胶 果胶裂解酶 VcPLs 基因克隆 

分 类 号：S663.9[农业科学—果树学]