A novel DNA damage checkpoint involving post-transcriptional regulation of cyclin A expression

J Biol Chem. 2000 Jan 21;275(3):1715-22. doi: 10.1074/jbc.275.3.1715.

Abstract

The intracellular metabolism of many carcinogenic polycyclic aryl hydrocarbons (PAHs, typified by the ubiquitous pollutant benzo[a]pyrene or B[a]P) generates electrophilic products that react covalently with genomic DNA. Cells that acquire PAH-induced DNA damage undergo growth arrest in a p53-independent manner (Vaziri, C., and Faller, D. V. (1997) J. Biol. Chem. 272, 2762-2769). In this report we have investigated the molecular basis of PAH-induced cell cycle arrest. Mitogenic signaling events involving cyclins D and E, Rb phosphorylation, and transcriptional activation of E2F-responsive genes (including cyclin E and cyclin A) were unaffected in cells containing PAH-damaged DNA. However, PAH-induced growth arrest was associated with post-transcriptional decreases in cyclin A expression. Mitogen-induced expression of cyclin B, an event that is temporally distal to cyclin A expression, was also inhibited in PAH-treated cells. The PAH-induced cell cycle block was transient, and arrested cells resumed DNA synthesis after a prolonged ( approximately 20 h) delay. Resumption of DNA synthesis in PAH-treated cells occurred concomitant with elevated expression of cyclins A and B. PAH-induced cell cycle arrest was overcome by ectopically expressed cyclin A (encoded by a recombinant adenovirus in transiently infected cells). Overall, our results suggest the existence of a DNA damage checkpoint pathway that arrests cell cycle progression via post-transcriptional control of cyclin A expression.

Publication types

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

MeSH terms

  • 3T3 Cells
  • Animals
  • Benzo(a)pyrene / toxicity
  • Carrier Proteins*
  • Cell Cycle / drug effects
  • Cell Cycle Proteins*
  • Cyclin A / genetics
  • Cyclin A / metabolism*
  • Cyclin D1 / metabolism
  • DNA Damage*
  • DNA-Binding Proteins*
  • E2F Transcription Factors
  • Flow Cytometry
  • Gene Expression Regulation*
  • Immunoblotting
  • Mice
  • Mitogens / metabolism
  • Mutagens / toxicity
  • Polycyclic Compounds / toxicity
  • RNA Processing, Post-Transcriptional*
  • Retinoblastoma Protein / metabolism
  • Retinoblastoma-Binding Protein 1
  • Signal Transduction / drug effects
  • Transcription Factor DP1
  • Transcription Factors / metabolism

Substances

  • Arid4a protein, mouse
  • Carrier Proteins
  • Cell Cycle Proteins
  • Cyclin A
  • DNA-Binding Proteins
  • E2F Transcription Factors
  • Mitogens
  • Mutagens
  • Polycyclic Compounds
  • Retinoblastoma Protein
  • Retinoblastoma-Binding Protein 1
  • Transcription Factor DP1
  • Transcription Factors
  • Cyclin D1
  • Benzo(a)pyrene