Molecular Cloning And Expression Analysis Of The Aqp1aa Gene In Half-Smooth Tongue Sole (Cynoglossus Semilaevis)

Aquaporin 1 (AQP1) is a member of the transmembrane water channel family of proteins with special structural features, and two AQP1 paralogous genes (aqplaa and aqplab) are reported in teleosts. In the present study, the aqplaa gene of half-smooth tongue sole (Cynoglossus semilaevis) was cloned and characterized. The full-length cDNA of aqplaa is 1411 bp with a 786 bp open reading frame encoding a 261-amino acid putative protein with a characteristic structure consisting of 6 membrane-spanning alpha-helical domains and two highly conserved asparagine proline alanine motifs. Real-time quantitative PCR revealed that aqplaa mRNA is expressed predominantly in the testis of males and pseudo males, while its expression is low in the ovary and lowest in doublesex and mab-3-related transcription factor 1 (DMRT1) knock out fish and triploid males. In situ hybridization indicated that aqplaa mRNA is expressed mainly in the germ cells of males and pseudo-males, especially in spermatozoa and spermatids. These results suggest that the aqplaa may play a role in spermatogenesis of C. semilaevis.