Induction of the BRCA2 promoter by nuclear factor-κB

Kangjian Wu, Shi Wen Jiang, Muthusamy Thangaraju, Guojun Wu, Fergus J. Couch

Research output: Contribution to journalArticle

34 Scopus citations

Abstract

BRCA2 is a tumor suppressor gene that has been implicated in response to DNA damage, cell cycle control, and transcription. BRCA2 has been found to be overexpressed in many breast tumors, suggesting that altered expression of the BRCA2 gene may contribute to breast tumorigenesis. To determine how BRCA2 is overexpressed in tumors, we investigated the transcriptional regulation of the BRCA2 promoter. Deletion mapping of the BRCA2 promoter identified three regions associated with 3-fold activation or repression and one upstream stimulatory factor binding site associated with 20-fold activation. Gel shift and cotransfection studies verified the role of USF in regulation of BRCA2 transcription. Analysis of the -144 to -59 region associated with 3-fold activation identified a putative NFκB binding site. Cotransfection of the p65 and p50 subunits of NFκB up-regulated the BRCA2 promoter 16-fold in a luciferase reporter assay, whereas mutations in the binding site ablated the effect. Gel shift and supershift assays with anti-p65 and -p50 antibodies demonstrated that NFκB hinds specifically to the NFκB site. In addition, ectopic expression of NFκB resulted in increased levels of endogeneous BRCA2 expression. Thus, NFκB and USF regulate BRCA2 expression through the BRCA2 promoter.

Original languageEnglish (US)
Pages (from-to)35548-35556
Number of pages9
JournalJournal of Biological Chemistry
Volume275
Issue number45
DOIs
StatePublished - Nov 10 2000
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Induction of the BRCA2 promoter by nuclear factor-κB'. Together they form a unique fingerprint.

  • Cite this