title: [Cloning of the cDNA of human PD-L1 gene and the expression of its extracellular domain in Escherichia coli].
abstract: OBJECTIVE
  To clone human PD-L1 cDNA and construct a prokaryotic expression vector for the extracellular domain of PD-L1 gene.
  
  
  METHODS
  The human PD-L1 cDNA was cloned by RT-PCR from the total RNA of activated human peripheral lymphocytes. The prokaryotic expression vector for the extracellular domain of PD-L1 gene was constructed and protein expression in E.coli strain BL21(DE3) was determined.
  
  
  RESULTS
  The full-length gene coding sequence of PD-L1 was cloned and confirmed by DNA sequencing. The prokaryotic expression vector for the extracellular domain of PD-L1 gene fused with His(6) tag at the C-terminus was then constructed. The recombinant protein was expressed in E.coli after IPTG induction and identified by Western blot. The expressed product had a relative molecular mass (M(r)) being 22 000, which was consistent with theoretical value.
  
  
  CONCLUSIONS
  The PD-L1 gene was successfully cloned and the extracellular domain of the protein was expressed in E.coli, which lays the foundation for further study of the function of PD-L1.
authors.affiliation: Key Laboratory of Tissue Transplantation and Immunology, Ministry of Education, Jinan University, Guangzhou 510632, China. ozms@jnu.edu.cn
authors.forename: Xian-hui
authors.initials: XH
authors.lastname: He
authors.forename: Li-hui
authors.initials: LH
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiao-chang
authors.initials: XC
authors.lastname: Cai
authors.forename: Yao-ying
authors.initials: YY
authors.lastname: Zeng
mesh_terms: D015703:Antigens, CD; D018122:B7-1 Antigen / Q000235:genetics* / Q000378:metabolism; D060890:B7-H1 Antigen; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005822:Genetic Vectors; D006639:Histidine; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D009842:Oligopeptides; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D060890:B7-H1 Antigen; C423236:CD274 protein, human; D018076:DNA, Complementary; C471213:His-His-His-His-His-His; D008562:Membrane Glycoproteins; D009842:Oligopeptides; D010455:Peptides; D011993:Recombinant Fusion Proteins; D006639:Histidine