西方蜜蜂Sirtuin蛋白家族基因鉴定及表达分析

Identification and Expression Analysis of Sirtuin Protein Family Genes in Apis mellifera

Sirtuin蛋白是一类进化保守的NAD+依赖性脱酰基酶家族,可调控生物的新陈代谢、基因组稳定性和寿命。为探究西方蜜蜂Sirtuin蛋白家族基因种类、分布和分子特征,以及不同级型、不同发育时期的表达模式,基于西方蜜蜂全基因组数据,采用生物信息学方法对西方蜜蜂Sirtuin蛋白家族成员进行鉴定,预测家族基因的结构和染色体位置,分析家族基因的结构域和系统发育关系;采用qRT-PCR分析Sirtuin蛋白家族基因在西方蜜蜂雌性蜂不同发育时期的表达情况。结果表明,在西方蜜蜂全基因组中鉴定出10个Sirtuin蛋白基因,属于6个家族成员(AmSirt1、AmSirt2、AmSirt4~AmSirt7),AmSirt1和AmSirt2家族成员各包含3个基因。6个家族成员基因分别定位于不同的染色体上,其中AmSirt1和AmSirt2呈现典型的串联重复分布,AmSirt1、AmSirt6和AmSirt7主要定位于胞质/细胞核,AmSirt2和AmSirt5主要定位于胞质,AmSirt4定位于线粒体。西方蜜蜂Sirtuin蛋白家族基因的编码氨基酸数为265~899个,分子质量为29.45~102.91 ku,等电点为4.58~9.09,外显子数为4~9个,内含子长56~2719 bp,Sirtuin蛋白家族基因包含12个保守结构域,并发现3个西方蜜蜂所特有的保守氨基酸位点。Sirtuin蛋白家族基因鉴定和系统发育关系表明,西方蜜蜂缺少Sirt3基因,10个Sirtuin蛋白基因聚合为4类6个分支,与东方蜜蜂、大蜜蜂的同源性较高。6个家族基因在蜂王和工蜂不同发育时期均有表达,蜂王整体基因表达量高于工蜂,各家族基因表达量均在2日龄蛹达到峰值。综上表明,西方蜜蜂有6个Sirtuin蛋白家族成员,系统进化中分为4类,缺少Sirt3家族成员。推测在西方蜜蜂雌性蜂不同发育时期,Sirtuin蛋白基因表达受禁食行为、热量限制和器官分化的影响。

Sirtuin proteins are evolutionarily conserved family of NAD+-dependent deacylases,which can regulate the metabolism,stress response,genomic stability and lifespan of organisms.In order to explore the species,distribution and molecular characteristics of Sirtuin protein family genes in Apis mellifera,and expression patterns of different castes and developmental stages,the bioinformatics methods were used to identify the members of Sirtuin protein family in A.mellifera topredict the structure and chromosomal location and analyze the structural domain and phylogenetic relationship of the family genes based on the whole genome data.Moreover,qRT-PCR was used to analyze the expression of Sirtuin protein family genes at different developmental stages of female bees.The results showed that ten Sirtuin protein genes were identified in the whole genome of A.mellifera,which belonged to six family members(AmSirt1,AmSirt2,AmSirt4 to AmSirt7).Each of the AmSirt1 and AmSirt2 family members contained three genes.The six family member genes were located on different chromosomes,among which AmSirt1 and AmSirt2 showed typical tandem repeat distribution,AmSirt1,AmSirt6 and AmSirt7 were mainly located in the cytoplasm/nucleus,AmSirt2 and AmSirt5 were mainly located in the cytoplasm,and AmSirt4 was located in the mitochondria.The number of encoded amino acids of Sirtuin protein family genes was 265-899,the molecular weight was 29.45-102.91 ku,the isoelectric point was 4.58-9.09,the number of exons was 4-9,and the intron length was 56-2719 bp,the Sirtuin protein family genes containedtwelve conserved domains,and three unique conserved amino acid sites of A.mellifera were found.The identification and phylogenetic relations hip of Sirtuin protein family genesshowed that A.mellifera lacked the Sirt3 gene,and ten Sirtuin protein genes were aggregated into four classes and six branches,which had high homology with A.cerana and A.dorsata.The six family genes were expressed at different developmental stages of queen and worker,the overall gene expression of queen was higher thanthat of the workers,and the expression of each family gene expression reached the peak at 2-day-old pupae.In conclusion,A.mellifera have six members of the Sirtuin protein family,which are divided into four classes in phylogeny,and lack the Sirt3 family.It is speculated that the expression of Sirtuin protein genes were affected by fasting behavior,calorie restriction and organ differentiation during different developmental stages of female bee in A.mellifera.