Biosynthesis of DNA polymerase beta in chick embryonic cells

J Biol Chem. 1982 Apr 10;257(7):3932-6.

Abstract

A monospecific antibody to chick embryo DNA polymerase beta was prepared from a rabbit immunized with the homogeneous enzyme preparation. The antibody has high neutralizing ability to the enzyme activity and, in the presence of formalin fixed Staphylococcus aureus, precipitates a Mr = 40,000 polypeptide from the crude extract and the partially purified DNA polymerase beta which were prepared from [35S]methionine-labeled chick embryonic cells. Pulse-chase experiments were carried out to clarify the process of the biosynthesis of DNA polymerase beta. We have attempted to detect a precursor polypeptide which would be expected to have the following properties: 1) a polypeptide which is specifically precipitated by the antibody and has a molecular weight different from 40,000, 2) the amount of the 35S-labeled polypeptide decreases in the chase period, and 3) 35S-labeled polypeptide which is eliminated from the immunoprecipitate by adding an excess amount of purified unlabeled DNA polymerase beta. However, no such polypeptide was detected in the 30-min pulse-labeled cells. A Mr = 40,000 polypeptide was immunoprecipitated from the extract of 30-min pulse-labeled cells and its amount did not change in a 5-hr chase, then decreased. Results suggest that a Mr = 40,000 polypeptide of chick embryo DNA polymerase beta is the initial translation product of the mRNA of DNA polymerase beta.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen-Antibody Complex
  • Chick Embryo
  • DNA Polymerase I / biosynthesis*
  • DNA Polymerase I / genetics
  • DNA Polymerase I / isolation & purification
  • DNA-Directed DNA Polymerase / biosynthesis*
  • Immune Sera
  • Immunodiffusion
  • Kinetics
  • Molecular Weight
  • Protein Biosynthesis
  • RNA, Messenger / genetics

Substances

  • Antigen-Antibody Complex
  • Immune Sera
  • RNA, Messenger
  • DNA Polymerase I
  • DNA-Directed DNA Polymerase