Title

Transcriptional corepressor TLE1 functions with Runx2 in epigenetic repression of ribosomal RNA genes

UMMS Affiliation

Department of Cell Biology; Department of Physiology

Date

2-18-2010

Document Type

Article

Medical Subject Headings

Cell Line, Tumor; *Epigenesis, Genetic; Humans; Immunoprecipitation; Microscopy, Fluorescence; Nucleolus Organizer Region; RNA, Ribosomal; Repressor Proteins; *Transcription, Genetic

Disciplines

Cell Biology

Abstract

Epigenetic control of ribosomal RNA (rRNA) gene transcription by cell type-specific regulators, such as the osteogenic transcription factor Runx2, conveys cellular memory of growth and differentiation to progeny cells during mitosis. Here, we examined whether coregulatory proteins contribute to epigenetic functions that are mitotically transmitted by Runx2 in osteoblastic cells. We show that the transcriptional corepressor Transducin Like Enhancer-1 (TLE1) associates with rRNA genes during mitosis and interphase through interaction with Runx2. Mechanistically, depletion of TLE1 relieves Runx2-mediated repression of rRNA genes transcription and selectively increases histone modifications linked to active transcription. Biologically, loss of TLE-dependent rRNA gene repression coincides with increased global protein synthesis and enhanced cell proliferation. Our findings reinforce the epigenetic marking target genes by phenotypic transcription factors in mitosis and demonstrate a requirement for retention of coregulatory factors to sustain physiological control of gene expression during proliferation of lineage committed cells.

Rights and Permissions

Citation: Proc Natl Acad Sci U S A. 2010 Mar 2;107(9):4165-9. Epub 2010 Feb 16. Link to article on publisher's site

Related Resources

Link to Article in PubMed