State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning 530004, Guangxi, China.
Fish Physiol Biochem. 2013 Aug;39(4):931-40. doi: 10.1007/s10695-012-9752-8. Epub 2012 Dec 7.
The full length of vasa cDNA in blue tilapia Oreochromis aureus was cloned and sequenced using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Nucleotide sequence analysis revealed that the cDNA contained 2,143 bp and was consisted of a 48-bp 5' untranslated terminal region (5'-UTR), a 157-bp 3' untranslated terminal region (3'-UTR) and a 1,938-bp open reading frame (ORF) which encoded 645 amino acids. Homological protein analysis showed that vasa in O. aureus was highly conserved with Nile tilapia Oreochromis niloticus. Tissue distribution expression analysis indicated that vasa was specifically expressed in the gonads. Using in situ hybridization, we found that vasa was expressed in spermatogonia and spermatocytes rather than spermatids and sperm. In order to examine the influence of luteinizing hormone releasing hormone analog (LHRH-A) on vasa, the in vivo injections were performed different concentrations of LHRH-A. Our results showed that LHRH-A induced meiosis and down-regulated vasa mRNA expression. In summary, our results showed that vasa was specifically expressed in gonads and LHRH-A inhibited vasa expression in the testis. Our results also suggested that LHRH-A could regulate vasa gene expression in O. aureus testis.
利用反转录聚合酶链式反应（RT-PCR）和快速扩增 cDNA 末端（RACE）技术，克隆并测序了蓝罗非鱼 Oreochromis aureus 的全长 vasa cDNA。核苷酸序列分析表明，该 cDNA 包含 2143bp，由 48bp 的 5'非翻译末端区（5'-UTR）、157bp 的 3'非翻译末端区（3'-UTR）和 1938bp 的开放阅读框（ORF）组成，ORF 编码 645 个氨基酸。同源蛋白分析表明，O. aureus 的 vasa 与尼罗罗非鱼 Oreochromis niloticus 高度保守。组织分布表达分析表明，vasa 特异性表达于性腺。通过原位杂交，我们发现 vasa 在精原细胞和精母细胞中表达，而不在精细胞和精子中表达。为了研究促黄体生成素释放激素类似物（LHRH-A）对 vasa 的影响，我们进行了不同浓度 LHRH-A 的体内注射实验。结果表明，LHRH-A 诱导了减数分裂，并下调了 vasa mRNA 的表达。综上所述，我们的结果表明，vasa 特异性表达于性腺，而 LHRH-A 抑制了睾丸中 vasa 的表达。我们的结果还表明，LHRH-A 可能在 O. aureus 睾丸中调节 vasa 基因的表达。
