中华按蚊OCT家族基因的多样性及序列特征

Diversity and sequence characteristics of the OCT family genes in Anopheles sinensis(Diptera:Culicidae)

【目的】在全基因组水平鉴定、分类和命名中华按蚊Anopheles sinensis有机阳离子转运体(organic cation transporter,OCT)家族基因,为昆虫OCT基因提供信息框架。【方法】从NCBI,VectorBase和EMBL数据库下载冈比亚按蚊An.gambiae、黑腹果蝇Drosophila melanogaster和秀丽隐杆线虫Caenorhabditis elegans已知的OCT氨基酸序列作为询问序列,基于中华按蚊基因组与转录组测序数据,通过本地Blast搜索鉴定中华按蚊基因组上OCT基因;运用生物信息学方法预测中华按蚊OCT基因的基因结构、Scaffold定位和保守基序等特征,通过最大似然法构建中华按蚊OCT基因的系统发育树。【结果】中华按蚊共有54个OCT家族基因,分属于OCTA,OCTB和OCTC 3个亚家族,分别有33,15和6个基因。除AsOCTA20和AsOCTB2外,其余OCT基因编码的氨基酸序列均具有MFS_1和Sugar_tr跨膜结构域(transmembrane domain,TMD),大多数OCT氨基酸序列有12个TMD。所有OCT氨基酸序列都有GRK-(PT)-VL,PES-(APVS)和EQFPT-(VI)-RN 3个保守基序,各亚家族还有各自的保守基序。4对基因(AsOCTB4a和AsOCTB4b,AsOCTA10a和AsOCTA10b,AsOCTA19a和AsOCTA19b,以及AsOCTA23a和AsOCTA23b)源自基因重复事件。AsOCTC基因较为原始,AsOCTB基因较为进化,都是明显的单系;AsOCTA基因介于两者之间,进化关系较为复杂。【结论】本研究丰富了中华按蚊基因组数据,为后续中华按蚊OCT基因功能特别是杀虫剂抗性机制方面的功能研究奠定了基础。

【Aim】To identify,classify and name genes of the organic cation transporter(OCT)family of Anopheles sinensis at the whole-genome level,so as to provide an information frame for the OCT genes of insects.【Methods】The amino acid sequences encoded by OCT genes in An.gambiae,Drosophila melanogaster and Caenorhabditis elegans were downloaded from NCBI,VectorBase and EMBL databases,and used as queries to search for the OCT genes in An.sinensis genome using the local Blast program based on the genome and transcriptome sequencing data of An.sinensis.The characteristics of these OCT genes in An.sinensis,including the gene structure,Scaffold location and conservative motifs,were predicted using bioinformatics methods.The phylogenetic tree of OCT genes of An.sinensis was constructed by the maximum likelihood method.【Results】The An.sinensis genome contains 54 OCT genes,which are divided into three subfamilies,OCTA,OCTB and OCTC,with 33,15 and 6 genes,respectively.The encoded OCT amino acid sequences,except for AsOCTA20 and AsOCTB2,have MFS_1 and Sugar_tr transmembrane domains(TMDs),and most of the OCT amino acid sequences have 12 TMDs.All the OCT amino acid sequences have three conserved motifs,GRK-(PT)-VL,PES-(APVS)and EQFPT-(VI)-RN,and each subfamily has its own conservative motifs.Four pairs of genes(AsOCTB4a and AsOCTB4b,AsOCTA10a and AsOCTA10b,AsOCTA19a and AsOCTA19b,and AsOCTA23a and AsOCTA23b)are derived from gene duplication events.AsOCTC genes are relatively primitive,while AsOCTB genes are relatively evolved,both forming an obvious monophyly.AsOCTA genes are between AsOCTC genes and AsOCTB genes in evolution,with more complicated evolutionary relationship.【Conclusion】This study enriches the genome data of An.sinensis,and lays the foundation for the subsequent research of the functions of OCT genes in An.sinensis,especially their functions in insecticide resistance mechanism.