Endothelial plasminogen activator inhibitor (PAI): a new member of the Serpin gene family

EMBO J. 1986 Oct;5(10):2539-44.


A human endothelial cDNA expression library, based on the Escherichia coli plasmid pUC9, was screened with a heterologous antibody raised against purified bovine aortic endothelial plasminogen activator inhibitor (PAI). A synthetic oligonucleotide, derived from a partial PAI cDNA expression clone, was used to select a full-length PAI cDNA, the size of which coincides with the length of PAI mRNA (approximately 2350 nucleotides) as determined by Northern blot analysis. The authenticity of full-length PAI cDNA is demonstrated by the expression of biologically active PAI both in lysates of transformed E. coli cells and in conditioned media of mouse Ltk- cells, transfected with PAI cDNA inserted into vector pSV2. Analysis of the de novo synthesized anti-plasminogen activator activity, employing reverse fibrin autography, shows that transfected mouse Ltk- cells synthesize a polypeptide with a mol. wt identical to that of the native PAI glycoprotein (Mr 52,000), whereas in E. coli an unglycosylated, active product with a mol. wt of 43,000 is made. The amino acid sequence, derived from the determined nucleotide sequence, shows that pre-PAI consists of 402 amino acids. It is proposed that the mature PAI is preceded by a signal peptide of 23 amino acid residues. The amino acid sequence of mature PAI includes three potential asparagine-linked glycosylation sites and lacks cysteine residues. The predicted amino acid sequence reveals significant homology with members of the serine protease inhibitor (Serpin) family, e.g. alpha 1-proteinase inhibitor and antithrombin III.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cells, Cultured
  • Cloning, Molecular
  • DNA / metabolism
  • Endothelium / metabolism*
  • Escherichia coli / genetics
  • Genes*
  • Glycoproteins / genetics*
  • Glycoproteins / metabolism
  • Humans
  • Plasmids
  • Plasminogen Inactivators
  • Poly A / isolation & purification
  • Protease Inhibitors / genetics*
  • RNA / isolation & purification
  • RNA, Messenger


  • Glycoproteins
  • Plasminogen Inactivators
  • Protease Inhibitors
  • RNA, Messenger
  • Poly A
  • RNA
  • DNA

Associated data

  • GENBANK/X04429