Abstract:

 【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.

Key words: Anopheles sinensis, organic cation transporter family, genome-wide identification, sequence conservativeness, phylogenetics