title: [Cloning, expression and purification of human PNAS-4].
abstract: 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.
  
  
  CONCLUSIONS
  Human PNAS-4 is expressed and purified successfully, which would ba a foundation for further research on the function of human PNAS-4 gene.
authors.affiliation: State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Cao
authors.forename: Chao
authors.initials: C
authors.lastname: Lin
authors.forename: Qian
authors.initials: Q
authors.lastname: Dai
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Ting-Jun
authors.initials: TJ
authors.lastname: Lei
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
authors.forename: Ming-Hai
authors.initials: MH
authors.lastname: Tang
authors.forename: Zhu
authors.initials: Z
authors.lastname: Yuan
mesh_terms: D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification*; D019759:Carbon-Nitrogen Lyases; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005822:Genetic Vectors / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology; D013058:Mass Spectrometry; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D051017:Apoptosis Regulatory Proteins; D011993:Recombinant Fusion Proteins; D019759:Carbon-Nitrogen Lyases; C000604991:DESI2 protein, human