Cloning and Expression Profiling of the Gene vasa during First Annual Gonadal Development of Cobia (Rachycentron canadum)

The vasa gene is essential for germ cell development and gametogenesis both in vertebrates invertebrates. In the present study, (Rcvasa) cDNA was cloned from cobia (Rachycentron canadum) using RACE amplification method. We found that full-length sequence of Rcvasa comprises 2571 bp, containing a 5′-UTR 145 3′-UTR 341 an open reading frame (ORF) 2085 encoding protein 694 aa. deduced amino acid contains 8 conserved motifs DEAD-box family, 7 RGG repeats, 10 RG repeats N-terminal region. Comparisons with those other teleosts revealed highest percentage identity (86.0%) Seriola quinqueradiata. By semiquantitative RT-PCR, appeared to be specifically expressed testis ovary, among 13 tissues analyzed. addition, annual changes expression levels were examined gonads by quantitative real-time PCR (qRT-PCR). first increased significantly at 120 dph (stage II–III), then stabilized as developed 185 III) 360 V). During ovary I II), reached level 210 decreased. Furthermore, results chromogenic situ hybridization (CISH) mRNA mainly cells barely detected somatic cells. testis, signal concentrated periphery spermatogonia, primary spermatocytes, secondary spermatocytes weaker spermatids spermatozoa. uniformly distributed perinuclear cytoplasm intense early oocytes II). These findings could provide reference understanding regulatory mechanisms during cobia.