缩骨鲫MSTN基因的克隆与组织表达分析

采用同源克隆、生物信息学方法及荧光定量PCR(Real-time PCR)对缩骨鲫(Carassius auratus sogu var.)肌肉生长抑制素(myostatin,MSTN)基因进行克隆,分析和组织表达状况研究。结果显示:缩骨鲫基因组MSTN基因全长4 737 bp,含有两个内含子和三个外显子;编码区长度为1 128 bp,编码375个氨基酸,包括信号肽(1aa~23aa),TGF-β前肽保守区域(34aa~256aa),TGF-β功能区(281aa~375aa),保守的RXXR蛋白酶酶切位点以及C-端活性区域9个保守的半胱氨酸残基,这与其他物种MSTN相似。此外,缩骨鲫与鲫鱼(Carassius auratus)的MSTN氨基酸序列同源性最高,达到96.1%。以β-actin为内参基因,荧光定量PCR分析表明,MSTN在肌肉中表达量最高;脑、眼、心脏中次之;在肝胰脏、卵巢、肠和肾脏中微量表达。

Cloning and tissues expression analysis of MSTN gene in Carassius auratus sogu var.

The myostatin ( MSTN) gene in Carassius auratus sogu var. was cloned and analyzed through homology-based cloning, bioinformatics technology and Real-time PCR. The result revealed that the length of MSTN of C. auratus sogu var. is 4737bp. It includes 3 exons and 2 introns. The length of coding sequence (CDS) is 1128bp, the gene code 375 ami-no acids which contain a signal peptide (1aa~23aa), a conserved propeptide domain (34aa~256aa), a functional do-main (281aa~375aa), a RXXR proteolysis site and nine conserved cysteine residues of C-terminal functional domain;As other species, the protein of MSTN have a TGF-β superfamily domain in C. auratus sogu var.; Compared with other species, the homology of MSTN amino acid sequences between C. auratus sogu var. and C. auratus is closer. Using Real-Time PCR detected MSTN mRNA expression of 9 tissues, the result suggested that the MSTN gene was highly expressed in muscle, second highly expressed in brain, eyes, heart and weakly expressed in ovary, hepatopancreas and kidneys.