目的:验证在HeLa细胞系中是否存在Zwint-1 v7选择性剪切亚型的mRNA和蛋白产物。方法:在缺失片段两侧设计引物,利用PCR和克隆测序验证HeLa细胞中是否存在缺失片段的mRNA;构建Zwint-1 v73′端特异区段(Z7)的GST融合表达载体pGEX-KG-GST-Z7,转化入BL21菌种诱导表达,菌体经超声破碎和2 mol/L尿素洗涤纯化,融合蛋白经SDS-PAGE电泳并切胶回收后作为抗原与佐剂混合乳化并免疫C57BL/6小鼠,收获多克隆抗血清Anti-Z7,采用Dot blot检测多克隆抗体的效价,Western blot检测HeLa细胞全蛋白中的Z7蛋白产物。结果:PCR和测序结果表明存在缺失37 bp的核酸片段;SDS-PAGE电泳显示在30.7 kDa处出现明显的蛋白条带;Dot blot结果表明1∶5000稀释的多克隆抗体能检出12 ng GST-Z7;Western blot结果表明,1∶200稀释的多克隆抗体可识别HeLa细胞中Zwint-1 v7蛋白。结论:本研究在核酸水平和蛋白水平初步验证了HeLa细胞中存在Zwint-1v7。
OBJECTIVE:To identify whether the mRNA and protein expression of Zwint-1 v7 existed in human cancer cell line. METHODS:To identify the mRNA with the deleted fragment in HeLa cells,we designed primers on the each side of the deleted fragment for PCR and sequencing. Therefore,we constructed prokaryotic expression vector pGEX-KG-GST-Z7,the inserted fragment Z7 was chosen basen on the different sequences between Zwint-1 and Zwint-1 v7. This vector was transformed into BL21 strain for the expression of fusion protein GST-Z7. After ultrasonication and purified from the SDS-PAGE gels,GST-Z7 was used as antigens and emulsified with adjuvants to immunize C57BL/6 female mice for the preparation of polyclonal antibody Anti-Z7. The serum titer was validated by Dol blot test. The Zwint-1 v7 protein in the total proteins of HeLa cells was evaluated by Western blot with Anti-Z7. RESULTS:The PCR and sequencing results showed mRNA with 37 bp deletions in HeLa cells. SDS-PAGE confirmed that GST-Z7 was correctly expressed in BL21 in the inclusion body. 12 ng GST-Z7 could be detected by the 5 000 times diluted Anti-Z7. Zwint-1 v7 from HeLa cells could be detected by the 200 times diluted Anti-Z7. CONCLUSION:We confirmed that Zwint-1 v7 protein existed in HeLa cells at the levels of translations of nucleic acid and protein structure.