Prohibitin is required for transcriptional repression by the WT1-BASP1 complex

Oncogene. 2014 Oct 23;33(43):5100-8. doi: 10.1038/onc.2013.447. Epub 2013 Oct 28.

Abstract

The Wilms' tumor-1 protein (WT1) is a transcriptional regulator that can either activate or repress genes controlling cell growth, apoptosis and differentiation. The transcriptional corepressor BASP1 interacts with WT1 and mediates WT1's transcriptional repression activity. BASP1 is contained within large complexes, suggesting that it works in concert with other factors. Here we report that the transcriptional repressor prohibitin is part of the WT1-BASP1 transcriptional repression complex. Prohibitin interacts with BASP1, colocalizes with BASP1 in the nucleus, and is recruited to the promoter region of WT1 target genes to elicit BASP1-dependent transcriptional repression. We demonstrate that prohibitin and BASP1 cooperate to recruit the chromatin remodeling factor BRG1 to WT1-responsive promoters and that this results in the dissociation of CBP from the promoter region of WT1 target genes. As seen with BASP1, prohibitin can associate with phospholipids. We demonstrate that the recruitment of PIP2 and HDAC1 to WT1 target genes is also dependent on the concerted activity of BASP1 and prohibitin. Our findings provide new insights into the function of prohibitin in transcriptional regulation and uncover a BASP1-prohibitin complex that plays an essential role in the PIP2-dependent recruitment of chromatin remodeling activities to the promoter.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Cell Nucleus / metabolism
  • Chromatin Assembly and Disassembly
  • Gene Expression Regulation, Neoplastic
  • HeLa Cells
  • Humans
  • K562 Cells
  • MCF-7 Cells
  • Membrane Proteins / metabolism*
  • Nerve Tissue Proteins / metabolism*
  • Phospholipids / metabolism
  • Prohibitins
  • Promoter Regions, Genetic
  • Repressor Proteins / metabolism*
  • Transcription, Genetic*
  • WT1 Proteins / genetics
  • WT1 Proteins / metabolism*

Substances

  • BASP1 protein, human
  • Membrane Proteins
  • Nerve Tissue Proteins
  • Phospholipids
  • Prohibitins
  • Repressor Proteins
  • WT1 Proteins
  • WT1 protein, human