AY358935基因真核表达质粒的构建及鉴定

Construction of an eukaryotic expression plasmid for AY358935 gene

目的构建AY358935基因的真核表达质粒并进行初步鉴定。方法以逆转录聚合酶链反应（reverse transcription—polymerase chain reaction，RT-PCR）扩增AY358935基因的cDNA，将该片段克隆进pGEM-Teasy载体；以测序正确的pGEM-T-AY重组质粒为模板构建pcDNA3．1-Ay真核表达质粒，并进行双酶切鉴定。以pcDNA3．1-Ay瞬时转染M14细胞，Western印迹法和3-（4，5-二甲基噻唑-2）-2，5-二苯基四氮唑溴盐[3-（4，5）-dimethylthiahiazo（-z-y1）-3，5-di_phenytetrazoliumromide，MTT]比色法分别检测转染细胞AY358935蛋白表达水平及细胞增殖力。结果RT-PCR扩增片段符合AY358935基因cDNA大小，与pcDNA3．1诅y克隆区酶切片段-致。对pGEM-T-AY质粒克隆区测序，结果也与AY358935基因cDNA序列相同。M14细胞分别转染AY358935基因、peDNA3．1和脂质体48h后，AY358935基因组蛋白表达水平明显高于其余两组，且AY358935基因组细胞A值（0．74）也明显高于其余两组（0．39和0．46），差异有统计学意义（P〈0．05）。结论AY358935基因的真核表达质粒pcDNA3．1-Ay构建成功，AY358935基因可能具有促进M14细胞增殖的作用。

Objective To construct an eukaryotic expression plasmid for AY358935 gene and explore its function. Methods eDNA of the AY358935 gene was amplified by reverse transcription-PCR and cloned into pGEM-Teasy. The pGEM-T-AY was validated by sequencing and served as a template for the construction of eukaryotic expression plasmid. The pcDNA3. 1-AY recombinant was validated by double enzyme digestion and used for transient transfection of M14 cells. Expression of the AY358935 protein and proliferation of the M14 ceils were determined respectively by Western blotting and 3-（ 4, 5 ）- dimethylthiahiazo（-z-yl）-3,5-di-phenytetrazoliumromide （MTT） colorimetry. Results The amplicons of RT-PCR were confirmed to have similar size with the cDNA fragment of the AY358935 gene as well as cloned region of pcDNA3. 1-AY. The cloned region of pGEM-T-AY was sequenced to be identical with cDNA sequence of the AY358935 gene. M14 cells were transfected by the AY358935 gene, pcDNA3.1 and liposomes, respectively. After 48 h, expression of the AY358935 protein in M14 cells transfected with the AY358935 gene was significantly higher than other two groups. They also had a significantly higher absorbance value （A= 0. 74） than other two groups （A： 0. 39 and 0. 46, respectively;P〈0. 05）. Conclusion An eukaryotic expression plasmid of the AY358935 gene was successfully constructed. Product of the AY358935 gene may promote the proliferation of M14 cells.