金钱鱼Dmrt5基因的克隆及表达分析

Cloning and Expression of Dmrt5 Gene in Scatophagus argus

为了解金钱鱼Dmrt5在性腺中的作用,克隆了金钱鱼Dmrt5,采用逆转录PCR检测了它的组织分布,并采用荧光定量PCR检测了Dmrt5在性腺和胚胎期中的表达模式.实验结果表明,金钱鱼Dmrt5的ORF全长为1347 bp,编码蛋白含448个氨基酸残基.同源性分析发现,金钱鱼Dmrt5与橙线雀的相似性最高为96. 0%,与人的相似性最低为68. 0%.通过系统进化分析可知金钱鱼Dmrt5与鲈形目鱼类Dmrt5为一类,与其进化地位一致.组织分布表明,金钱鱼Dmrt5在下丘脑和脑垂体中高表达.对性腺不同发育时期的表达分析发现,Dmrt5在Ⅲ期和Ⅳ期精巢中的表达显著高于Ⅴ期精巢,而在Ⅱ、Ⅲ、Ⅳ期卵巢间的表达无显著差异. Dmrt5在胚胎期各阶段都有表达,但差异不显著.金钱鱼Dmrt5可能具有性别调控和神经发生等功能.

In order to study the function of Dmrt5 in gonad,Dmrt5 gene in Scatophagus argus was cloned,then its expression in different tissues was examined by reverse-transcription(RT-PCR),and its expression in gonads and embryos at different developmental stages was examined as well by quantitative Real-time PCR(q PCR). The full-length ORF of Dmrt5 in S. argusis1 is 347 bp,encoding 448 amino acids. Homology analysis indicated that Dmrt5 in Acanthochromis polyacanthus is with the highest similarity of 96. 0% to that in S. argus,while human Dmrt5 is with the lowest similarityof 68. 0% to that in S. argus. Phylogeneticanalysis revealed that S. argus Dmrt5 is clustered with Dmrt5 in perciform fishes,which is consistent with their evolutionary status. Tissue distribution indicated high expression of Dmrt5 in the hypothalamus and pituitary gland. Dmrt5 was expressed higher in testis at stage Ⅲ and IV than at stage V,while its expression in ovaries showed no significant difference at stage Ⅱ,Ⅲ and Ⅳ. Meanwhile,Dmrt5 was expressed evenly in embryos at various stages. Dmrt5 may functionas a regulator of sex differentiation and neurogenesis in S. argus.