柚多聚半乳糖醛酸酶基因家族的鉴定和分析  

Identification and Analysis of polygalacturonasegenes Family in Pomelo

作　　者：刘若南 刘林婷 周秋蓉 张蓓 高志键 葛聪 庄木来 李延[3] 王平[1] LIU Ruonan;LIU Linting;ZHOU Qiurong;ZHANG Bei;GAO Zhijian;GE Cong;ZHUANG Mulai;LI Yan;WANG Ping(Institute of Genetics and Breeding in Horticultural Plants,College of Horticulture,Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China;Pinghe Agriculture Bureau of Fujian Province,Pinghe,Fujian 363700,China;College of Re-sources and Environment,Fujian Agriculture and Forestry University,Fuzhou,Fujian 350002,China)

机构地区：[1]福建农林大学园艺学院园艺植物遗传育种研究所,福建福州350002 [2]福建漳州市平和县农业局,福建平和363700 [3]福建农林大学资源与环境学院,福建福州350002

出　　处：《热带作物学报》2022年第4期666-674,共9页Chinese Journal of Tropical Crops

基　　金：国家现代农业(柑橘)产业技术体系专项(No.CARS-26);福建农林大学科技创新专项基金项目(No.KFA17111A,No.KFA17359A)。

摘　　要：草莓、桃、苹果等果实在生长后期和贮藏过程中逐渐软化,而柑橘类特别是柚在成熟后期和贮藏过程中出现粒化,严重影响其经济价值。本研究分析和鉴定了柚基因组中多聚半乳糖醛酸酶基因(CgPG)家族成员以及PG酶活的变化,旨在揭示柚果实成熟过程中CgPG表达与汁胞粒化形成的关系。本研究对柚基因组库中CgPG基因家族成员的数量、基因定位、基因结构进行生物信息学分析,并对CgPG基因家族成员进行了表达鉴定,同时测定了汁胞粒化程度以及PG活性。结果表明:从柚全基因组鉴定出26个CgPG基因,进化树分析聚类为6个亚类(Group A~Group F),除E类外,所有外显子,内含子结构和基序基本上都是保守的,Group E中的CgPG26的GDDC结构域突变为GDDA,SPNTDGI突变为APNTDGI;CgPG基因主要分布于1、2、4、5、7、9号染色体上,在2和5号染色体上都有5~6条基因的串联复制;Group A和Group B与果实成熟有关,Group A中的CgPG5和Group B中的CgPG1、CgPG24参与了果实成熟和汁胞软化,CgPG13、CgPG12、CgPG26参与柚粒化过程中的果胶降解和细胞壁稳态调节;通过表达分析,Group A中的CgPG5和Group B中的CgPG1、CgPG24可能参与了柚不易粒化果成熟过程中汁胞的软化和最后腐败,基因的显著表达表明汁胞走向衰败;GroupD中的CgPG13和GroupE中的CgPG12、CgPG263个基因可能参与了柚易粒化果成熟过程中的果胶暂时降解,基因的高表达使汁胞软化,此时正是食用的最佳时期,随后在汁胞粒化过程中基因表达显著下降。因此,CgPG基因表达呈现不同的趋势表明CgPG基因在不易粒化果和易粒化果中可能属于2个不同的调节系统,其中CgPG5、CgPG1、CgPG24属于柚成熟后期汁胞软化的果胶降解系统,CgPG13、CgPG12、CgPG26属于柚粒化的细胞壁稳态调节系统。Strawberry, peach, apple and some other fruits gradually soften in the late growth period and during storage,while citrus, especially pomelo, granulated in the later ripening and storage, which seriously affects its economic value.In this study, the members of CgPG gene family in the pomelo genome library and the changes of PG enzyme activity were investigated to reveal the relationship between CgPGs expression and juice sacs granulationin the ripening process of pomelo fruit. The number, location and structure of CgPG gene family members in pomelo genome library were analyzed by bioinformatics, and the expression of CgPG gene family members was identified. The degree of granulation and the activities of PG were determined. 26 CgPG genes from pomelo genome were clustered into 6 subgroups(group A-group F) by phylogenetic tree analysis. Except for class E, all exons and introns and motifs were essentially conservative. GDDC domain of CgPG26 in Group E was mutated to GDDA, and SPNTDGI was mutated to APNTDGI respectively. The CgPG genes were mainly distributed on chromosomes 1, 2, 4, 5, 7 and 9. There were 5-6 tandem duplications of genes on both chromosomes 2 and 5. Group A and group B were related to fruit ripening. CgPG5 in group A and CgPG1, CgPG24 in group B were involved in fruit ripening and juice sacs softening, and CgPG13, CgPG12, CgPG26were involved in pectin degradation and homeostatic regulation in cell wall during pomelo granulation. By expression analysis, CgPG5 in Group A and CgPG1, CgPG24 in Group B might be involved in softening and final decay during the ripening process of the non-granulated fruits, and the significant expression of the genes indicated the juice sacs were decomposed. CgPG5 in Group A and CgPG1, CgPG24 in Group B might be involved in the temporary degradation of pectin during the ripening process of easily granulated fruits. The high expression of the genes made juice sacs softened,which was the optimal time for consumption. The expressions of the genes were highly decreased during

关 键 词：柚 多聚半乳糖醛酸酶 汁胞软化 汁胞粒化 

分 类 号：S666.3[农业科学—果树学]