中华按蚊化学感受蛋白(CSP)家族基因的全基因组鉴定和特征分析  

Genome-wide identification and characterization of genes of the chemosensory protein( CSP ) family in Anopheles sinensis( Diptera:Culicidae)

作　　者：梅婷[1] 何正波[1] 王小婷[1] 王婷婷[1] 陈斌[1] 

机构地区：[1]重庆师范大学生命科学学院,昆虫与分子生物学研究所,媒介昆虫重庆市重点实验室,重庆401331

出　　处：《昆虫学报》2017年第2期136-147,共12页Acta Entomologica Sinica

基　　金：“两江学者”计划专项经费;国家自然科学基金项目(31672363,31372265);国际原子能机构CRP项目(18268);国家科技基础性工作专项重点项目(2015FY210300)

摘　　要：【目的】在全基因组水平鉴定中华按蚊Anopheles sinensis化学感受蛋白(chemosensory protein,CSP)家族基因,预测该家族基因的特征,研究代表性双翅目昆虫CSP基因的系统发育和进化。【方法】在NCBI数据库中下载CSP氨基酸序列作为询问序列,通过Blast和HMM方法在全基因组水平搜索和鉴定中华按蚊、冈比亚按蚊An.gambiae、埃及伊蚊Aedes aegypti和致倦库蚊Culex quinquefasciatus的CSP家族基因并命名;通过生物信息学方法预测中华按蚊CSP家族基因的特性(基因结构、基因组定位、剪切模式、Ka/Ks比值)、保守结构域和蛋白质结构等;通过MEGA软件用最大似然法(maximum likelihood,ML)推断该家族基因的系统发育。【结果】中华按蚊、冈比亚按蚊、埃及伊蚊和致倦库蚊基因组分别有8,8,43和27个CSP家族基因。中华按蚊CSP家族基因(AsCSPs)都有全长的转录组序列,编码116(AsCSP7)~335(AsCSP5)个氨基酸;7个AsCSPs分布于Scaffold51上,AsCSP8分布于Scaffold116;AsCSP1~AsCSP8分别有3,2,1,1,1,2,1和2个选择性剪切模式;AsCSP3的表达量最高,其FPKM值达到385.46。AsCSPs的N端信号肽由17~37个氨基酸组成,均含有4个保守的半胱氨酸位点(CYS68,CYS75,CYS94和CYS97),这些位点界定了两个二硫键(CYS68-CYS75和CYS94-CYS97)。系统发育分析结果显示,4种蚊虫的8个CSP基因各自形成明显的支系,被命名为组CSP1~CSP8(CSP1-CSP8 group)。埃及伊蚊和致倦库蚊分别有35和18个CSP基因形成了一个不为按蚊所共有的特殊支系,被命名为Culicinae-specific组。替换率结果显示,中华按蚊与冈比亚按蚊同源基因对的Ka/Ks值都小于1,说明CSP家族基因在进化过程中主要是受到纯化选择作用。【结论】本研究为蚊虫,特别是中华按蚊基因组CSP家族基因提供了信息框架,为进一步开展该家族基因的功能研究奠定了基础。【Aim】The study aims to identify the genes of the chemosensory protein（ CSP） family in Anopheles sinensis whole-genome,to predict the characteristics of these CSP genes,and to investigate the phylogenetics and evolution of the CSPs in representative dipteran species. 【Methods】We searched,identified and named the CSP genes in An. sinensis, An. gambiae, Aedes aegypti and Culex quinquefasciatus genomes with Blast and HMM methods using CSP amino acid sequences downloaded fromNCBI database as inquiry entry,analyzed the characteristics of the CSP genes in An. sinensis using bioinformatics methods,including the structure,location,splicing and Ka / Ks ratio of these genes,conservative domains and protein structures,and deduced the phylogeny of CSP genes using maximum likelihood（ ML） method with MEGA software. 【Results】The genomes of An. sinensis,An. gambiae,Ae. aegypti and Cx. quinquefasciatus contain 8,8,43 and 27 CSP genes,respectively. The CSP genes identified in An. sinensis（ AsCSPs） are all supported by full-length transcripts,encoding 116（ AsCSP7）to 335（ AsCSP5） amino acids. Out of them,seven AsCSPs are located on Scaffold 51 and AsCSP8 on Scaffold116. AsCSP1-AsCSP8 possess 3,2,1,1,1,2,1 and 2 splicing variants,respectively,and AsCSP3 shows the highest expression level with a FPKM value of 385. 46. All AsCSPs each has a Nterminal signal peptide consisting of 17-37 amino acids,and contains 4 conserved cysteine sites（ CYS68,CYS75,CYS94 and CYS97）,which define two disulfide bonds（ CYS68-CYS75 and CYS94-CYS97）. Phylogenetic analysis results showed that eight CSP genes in four mosquito species are each grouped into a significant clade,and were named as CSP1-CSP8 group,respectively. Thirty-five and 18 CSP genes in Ae. aegypti and Cx. quinquefasciatus,respectively,are grouped into a special clade without homologous genes with Anopheles species,and was named as the Culicinae-specific group in this study.The Ka / Ks values of orthologous gene pairs between An. sinensis and An. gambiae

关 键 词：中华按蚊 化学感受蛋白 全基因组鉴定 生物信息学 基因特征 系统发育 

分 类 号：Q966[生物学—昆虫学]