ETS-mediated cooperation between basic helix-loop-helix motifs of the immunoglobulin μ heavy-chain gene enhancer

Wei Dang, Xiao Hong Sun, Ranjan Sen

Research output: Contribution to journalArticle

Abstract

The μE motifs of the immunoglobulin μ heavy-chain gene enhancer bind ubiquitously expressed proteins of the basic helix-loop-helix (bHLH) family. These elements work together with other, more tissue-restricted elements to produce B-cell-specific enhancer activity by presently undefined combinatorial mechanisms. We found that μE2 contributed to transcription activation in B cells only when the μE3 site was intact, providing the first evidence for functional interactions between bHLH proteins. In vitro assays showed that bHLH zipper proteins binding to μE3 enhanced Ets-1 binding to μA. One of the consequences of this protein-protein interaction was to facilitate binding of a second bHLH protein, EA7, to the μE2 site, thereby generating a three-protein-DNA complex. Furthermore, transcriptional synergy between bHLH and bHLH zipper factors also required an intermediate ETS protein, which may bridge the transcription activation domains of the bHLH factors. Our observations define an unusual form of cooperation between bHLH and ETS proteins and suggest mechanisms by which tissue-restricted and ubiquitous factors combine to generate tissue-specific enhancer activity.

Original languageEnglish (US)
Pages (from-to)1477-1488
Number of pages12
JournalMolecular and Cellular Biology
Volume18
Issue number3
StatePublished - Mar 1998
Externally publishedYes

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cell Biology

Fingerprint Dive into the research topics of 'ETS-mediated cooperation between basic helix-loop-helix motifs of the immunoglobulin μ heavy-chain gene enhancer'. Together they form a unique fingerprint.

  • Cite this