Stimulation of DNA chain initiation by a protein factor (NPF-1) from rat liver of different ages

Prog Clin Biol Res. 1989:287:289-99.


DNA Polymerase-alpha/primase complexes have been isolated from human neuroblastoma IMR-32, embryonic chicken brains (ECB) and rat prostate tumor PA-3 cells. In the presence of (NH4)2SO4 the major part (90%) of primase activity is released from the Pol-alpha/primase complex. A novel hydrophobic interaction column was used for purification of the primase from PA-3 cells. A nuclear protein factor (NPF-1) that stimulates DNA pol-alpha/primase activity has been purified from rat liver of various ages (3-6 months). The nuclear protein factor which only stimulates the primase activity is under investigation. The monoclonal antibodies (SJK 132-20 and 237-71) were used to detect DNA pol-alpha polypeptides from 11- to 19-day-old embryonic chicken brains.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aging*
  • Amanitins / metabolism
  • Animals
  • Chromatin / isolation & purification
  • Chromosomal Proteins, Non-Histone / metabolism
  • DNA Helicases / metabolism
  • DNA Primase
  • DNA Replication*
  • DNA-Directed DNA Polymerase / blood
  • DNA-Directed DNA Polymerase / metabolism
  • Liver / enzymology*
  • Liver / metabolism
  • RNA Nucleotidyltransferases / analysis
  • RNA Nucleotidyltransferases / isolation & purification
  • RNA Nucleotidyltransferases / metabolism
  • Rats


  • Amanitins
  • Chromatin
  • Chromosomal Proteins, Non-Histone
  • DNA Primase
  • RNA Nucleotidyltransferases
  • DNA-Directed DNA Polymerase
  • DNA Helicases