RESUMO
OBJECTIVE: To clone a novel apoptosis-related gene, human PNAS-4, and to get it expressed in E. coli. METHODS: Human PNAS-4 gene was amplified by RT-PCR form A549 human lung adenocarcinoma cells and inserted into pGEX-6P-1 vector. The resulting recombinant plasmid was transformed into E. coli. BL21. Human PNAS-4 protein was expressed with IPTG induction and the purified protein was identified by SDS-PAGE and mass spectrometry. RESULTS: The sequence of the human PNAS-4 gene in the recombinant plasmid was identical with that published in GenBank. The purified fusion protein of human PNAS-4 with relative molecular mass of 50 000 Da was observed in SDS-PAGE analysis, and was identified to be human PNAS-4 by mass spectrometry. CONCLUSION: Human PNAS-4 is expressed and purified successfully, which would ba a foundation for further research on the function of human PNAS-4 gene.