日本囊对虾电压门控钠通道基因克隆与组织表达

利用基因克隆等分子生物学技术,获得日本囊对虾(Marsupenaeus ja ponicus)的电压门控钠通道(voltage-gate sodium channel,VGSC)蛋白的部分eDNA序列,获得的片段核苷酸长度为2 877 bp,可编码954个氨基酸残基,总分子质量约为108.2 ku.与同源蛋白比较结果显示,日本囊对虾的VGSC序列与其他一些物种具有较高相似性,特别是跨膜蛋白结构域具有极高的保守性.基于VGSC氨基酸序列比对绘制的系统树基本能够反映出各物种间的进化关系.以RT-PCR法检测日本囊对虾VGSC的组织表达,结果显示VGSC表达与各组织的功能有极其密切的关系.VGSC mRNA在脑神经节中表达量最高,其次为肝胰腺,说明了钠通道在神经信号传导以及调节内分泌中都起到了重要的作用.

Gene Cloning and Tissue Expression of Voltage-gate Sodium Channel from Marsupenaeus japonicus

Partial cDNA of VGSC(voltage-gate sodium channel)was cloned from Marsupenaeus japonicus using gene cloning method in this study.The length of partial VGSC cDNA was 2 877 bp,encoding polypeptide of 954 amino acids with calculated molecular mass of 108.2 ku.Amino acid sequence alignment showed that the M.japonicus VGSC was found to have high homology with that in some model animals,especially in the transmenbrane structural domain.Phylogenetic tree,based on comparison of VGSC proteins,was consistent with the evolution relationship.The tissue expressions in 6 different tissues were tested by RT-PCR.The results showed that the expected PCR products were amplified from 6 kinds of tested tissue,the highest expression of VGSC was found in brain,the following was in hepatopancreas,illuminating sodium channel might play an important role in signal transduction and neurosecretory.