p53-mediated downregulation of H ferritin promoter transcriptional efficiency via NF-Y

Int J Biochem Cell Biol. 2008;40(10):2110-9. doi: 10.1016/j.biocel.2008.02.010. Epub 2008 Feb 17.

Abstract

The tumor suppressor protein p53 triggers many of the cellular responses to DNA damage by regulating the transcription of a series of downstream target genes. p53 acts on the promoter of the target genes by interacting with the trimeric transcription factor NF-Y. H ferritin promoter activity is tightly dependent on a multiprotein complex called Bbf; on this complex NF-Y plays a major role. The aim of this work was to study the modulation of H ferritin expression levels by p53. CAT reporter assays indicate that: (i) p53 overexpression strongly downregulates the transcriptional efficiency driven by an H ferritin promoter construct containing only the NF-Y recognition sequence and that the phenomenon is reverted by p53 siRNA; (ii) the p53 C-terminal region is sufficient to elicitate this regulation and that a correct C-terminal acetylation is also required. The H ferritin promoter displays no p53-binding sites; chromatin immunoprecipitation assays indicate that p53 is recruited on this promoter by NF-Y. The p53-NF-Y interaction does not alter the NF-Y DNA-binding ability as indicated by electrophoretic mobility shift assay (EMSA) analysis. These results demonstrate that the gene coding for the H ferritin protein belongs to the family of p53-regulated genes, therefore adding a new level of complexity to the regulation of the H ferritin transcription and delineate a role for this protein in a series of cellular events triggered by p53 activation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoferritins / genetics*
  • CCAAT-Binding Factor / metabolism*
  • Chromatin Immunoprecipitation
  • Down-Regulation / drug effects
  • Down-Regulation / genetics*
  • Doxorubicin / pharmacology
  • Gene Expression Regulation, Neoplastic / drug effects
  • HCT116 Cells
  • HeLa Cells
  • Humans
  • Promoter Regions, Genetic / genetics*
  • Protein Binding / drug effects
  • Transcription, Genetic* / drug effects
  • Tumor Suppressor Protein p53 / antagonists & inhibitors
  • Tumor Suppressor Protein p53 / chemistry
  • Tumor Suppressor Protein p53 / metabolism*
  • p300-CBP Transcription Factors / metabolism

Substances

  • CCAAT-Binding Factor
  • Tumor Suppressor Protein p53
  • Doxorubicin
  • Apoferritins
  • p300-CBP Transcription Factors