Mechanism of inhibition of hepatic protein synthesis in rats by the carcinogen, methylazoxymethanol acetate

Dennis J. Grab, Amalia Pavlovec, Mary G. Hamilton, Morris S. Zedeck

Research output: Contribution to journalArticle

Abstract

Treatment of rats with the carcinogen, methylazoxymethanol acetate, results in a rapid, marked inhibition of hepatic protein synthesis and disaggregation of polysomes. Studies were undertaken to learn the mechanism by which this carcinogen induces these effects in rat liver. The data show that the inhibition of endogenous protein synthesis is not due to an effect on the high speed supernatant 'factors' but rather at the level of the polysome, and that both free and membrane-bound polysomes are affected. Poly(U)-directed polyphenylalanine synthesis by native ribosomal subunits is greater in preparations isolated from rats treated with carcinogen than it is in controls. Moreover, the native ribosomal subunit fraction from treated livers in response to added rabbit globin mRNA is able to synthesize a protein similar in molecular weight to globin. These studies show that methylazoxymethanol acetate does not induce significant alterations of ribosomal subunits or of initiation factors and suggest that the inhibition of protein synthesis and disaggregation of polysomes may be the results of an alteration of cytoplasmic mRNA, or its association with ribosomes.

Original languageEnglish (US)
Pages (from-to)240-252
Number of pages13
JournalBBA Section Nucleic Acids And Protein Synthesis
Volume563
Issue number1
DOIs
StatePublished - Jun 20 1979
Externally publishedYes

Keywords

  • (Rat liver)
  • Carcinogen inhibition
  • Methylazoxymethanol acetate
  • Protein synthesis

ASJC Scopus subject areas

  • Medicine(all)

Fingerprint Dive into the research topics of 'Mechanism of inhibition of hepatic protein synthesis in rats by the carcinogen, methylazoxymethanol acetate'. Together they form a unique fingerprint.

  • Cite this