›› 2015, Vol. 58 ›› Issue (2): 122-131.

• RESEARCH PAPERS • Previous Articles     Next Articles

Molecular cloning, characterization and expression analysis of sex determiantion gene  doublesex  from  Anonpheles gambiae  (Diptera: Culicidae)

LIU Pei-Wen#, LI Xiao-Cong#,GU Jin-Bao*, LIU Yan, CHEN Xiao-Guang   

  1.  (Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes, Department of Pathogen Biology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, China)
  • Online:2015-02-20 Published:2015-02-20

Abstract: 【Aim】 Doublesex (dsx) is a key gene involved in the sex determination system, which controls sex determination in the germ line and soma of insects. This study aims to obtain the full-length cDNA sequence of  dsx  from major malaria mosquito  Anopheles gambiae , to reveal the sex-specific differences in splicing patterns of dsx pre-mRNA, and to determine the expression profiles of  dsx  in different developmental stages. 【Methods】 The full-length cDNA of doublesex (Angdsx) were obtained from A. gambiae using RT-PCR and RACE methods. The motif prediction, multiple alignments of amino acid sequences and-phylogenetic analysis were conducted by corresponding bioinformatics softwares. RT-PCR analysis was performed to analyze its sex-specific and development-specific expression profiles. 【Results】 The full-length cDNA sequences of Angdsx  were cloned from female and male adults of A. gambiae, and named AngdsxM (GenBank accession no. KM978938) and AngdsxF (GenBank accession no. KM978937), respectively. Angdsx  covers an 80 kb genome region on chromosome 2R. AngdsxF and AngdsxM are 4 874 nt and 3 183 nt in length, encoding 265 and 633 amino acids, respectively. Besides the conserved motifs including TRA/TRA-2 binding site, dsx  repeat elements (dsx REs), arginine-serine rich protein, purine-rich enhancer and RNA-binding proteins target sequences, the GT repeat motifs were also indentified in Angdsx by meme program. Compared with AngdsxM,AngdsxF contains an extra female specific exon. RT-qPCR analysis displayed that the expression level of AngdsxM was higher in 0-2 h  embryo and then declined, but increased from 12-24 h embryo again, while that of AngdsxF raised from 6-8 h. 【Conclusion】 The full-length Angdsx gene was isolated and identified from A. gambiae, which shows conservation of functional domains and sex-specific splicing. This study contributes to understanding the sex differentiation in mosquitoes and may facilitate the application of transgenic mosquitoes based release of insects carrying a dominant lethal (RIDL) technology on vector control.

Key words: Anonpheles gambiae, sex-determining gene, doublesex, release of insects carrying a dominant lethal (RIDL), sequence analysis, expression profile