基于转录组的荔枝PG基因家族鉴定及表达分析

Identification and Expression Analysis of Litchi PG Gene Family based on Transcriptome

本研究利用转录组数据对荔枝的PG基因家族进行分析,以探究PGs基因在荔枝中存在的形式,及荔枝PG基因家族在荔枝果实衰老中的作用及表达规律。结果表明,(1)荔枝中存在21个PG基因家族成员,它们的理化性质差异较大,多数蛋白表现为酸性及亲水性,位于细胞外基质或细胞质膜上。(2)该基因家族成员都存在保守基序8和保守基序14,结构域SPNTDG(Ⅰ)、GDDC(Ⅱ)和RIK(Ⅳ),但缺失了结构域CGPGHG(Ⅲ)。(3)进化树显示该基因家族成员分为5个类群,其中GroupⅢ是主要类群,其他类群在进化过程中逐渐形成。(4)RT-qPCR结果表明该基因家族的蛋白在荔枝生长发育过程中发挥不同作用,研究发现PG3、PG12、PG15、PG21与果实的衰老有关,表达量随果实衰老进程加剧而不断升高,它们正向调控了果实的衰老。本研究初步探究了PG基因家族成员在荔枝果实衰老过程中的作用,找出了几个和果实衰老相关的PG基因,为进一步研究荔枝的生理提供参考。

In this study,transcriptome data were used to analyze PG gene family in litchi to explore the existing form of PGs gene in litchi and the role and expression of PG gene family in litchi fruit senescence.The results showed that,(1)There were 21 members of PG gene families in litchi,and their physical and chemical properties are different,most protein expression is acid and hydrophilic,located in the extracellular matrix or cytoplasmic membrane.(2)All members of the family of the gene are conservative motif 8 and 14,conservative motif structure domain SPNTDG(Ⅰ),GDDC(Ⅱ)and RIK(Ⅳ),but CGPGHG(Ⅲ)was missing.(3)Evolutionary tree showed that the members of the family of genes is divided into 5 groups,GroupⅢis the major group,other groups gradually formed in the process of evolution.(4)The results of qPCR indicated that the proteins of this gene family play different roles in the growth and development of litchi,in which PG3,PG12,PG15,PG21 is related to the aging of fruits,the expression level of which increases with the aggravation of the aging process of fruits,and they positively regulate the aging of fruits.In this study,the role of PG gene family members in the aging process of litchi fruit was preliminarily explored,and several PG genes related to fruit aging were found,providing reference for further study on the physiology of litchi.