黄姑鱼(Nibea albiflora)gsdf基因的克隆及表达分析

Cloning and Expression Analysis of gsdf Gene in the Yellow Drum(Nibea albiflora)

为探索gsdf(gonadal soma derived factor)基因对黄姑鱼性别分化和性腺发育的作用,克隆了黄姑鱼gsdf基因ORF序列全长,并运用实时荧光定量PCR(qRT-PCR)技术检测了该基因在黄姑鱼不同组织和不同发育时期性腺中的表达情况。结果显示:黄姑鱼gsdf基因开放阅读框长648 bp,可编码215个氨基酸,含有TGF-β超家族的保守功能结构域;组织表达分析结果显示,黄姑鱼gsdf基因主要集中在精巢中表达;在23℃左右水温下,孵化后40 d的遗传雄性鱼苗性腺中开始检测到gsdf基因有明显表达(此时组织学上尚看不出精巢形态),49 d后表达量迅速升高,孵化120 d后(精巢分化完成)表达量达到高峰,随后表达量开始下降,直到黄姑鱼精巢成熟之后呈现稳定表达。上述结果提示,黄姑鱼gsdf基因与黄姑鱼性别决定和分化发育过程密切相关。

In order to study the function of gsdf（ gonadal soma derived factor） in sex differentiation and gonad development in the yellow drum（ Nibea albiflora）, the ORF（ open reading frame） sequence of gsdf gene was obtained through molecular and bioinformatics technique. And the expression profile of gsdf in different tissues and different development stages of gonads was assayed by qRT-PCR（ quantitative real time PCR）. Results showed that the gsdf contained a 648 bp open reading frame encoding a protein of 215 amino acids with a conserved domain shared by the TGF-β superfamily. The qRT-PCR analysis revealed that gsdf mainly expressed in testis of the yellow drum. Hatching and rearing at 23 ℃,the gsdf expression in the genetic males was detected from 40 dph（ day post hatch） while the testis was unidentifiable by histology. The expression of gsdf went up rapidly after 49 dph,and reached to the maximum peak on 120 dph when the testis was fully differentiated. Subsequently,the expression of gsdf showed down-regulation and it tended to be stabilized after the testis was fully mature. These results indicated that gsdf was tightly related to the testis differentiation and development in N. albiflora.