The disordered amino-terminus of SIMPL interacts with members of the 70-kDa heat-shock protein family

Erin Haag Breese, Vladimir N. Uversky, Millie M. Georgiadis, Maureen A. Harrington

Research output: Contribution to journalArticle

9 Scopus citations


The p65 coactivator SIMPL is a small protein that lacks any conserved domains of known function. To better understand regulation of SIMPL activity, we sought to identify novel SIMPL interacting proteins using mass spectrometry analysis of SIMPL containing complexes. Two members of the 70-kDa heat-shock protein family, Hsp70 and Hsc70, were identified as SIMPL binding proteins. Subsequent immunocomplexing assays confirmed this interaction and demonstrated that the amino-terminus of SIMPL is required for this interaction. Using a combination of amino acid composition analysis, PONDR® VL-XT prediction, charge-hydropathy plots, and cumulative distribution functions, the amino-terminal region of both mouse and human SIMPL proteins was predicted to be intrinsically disordered. These data, taken together, suggest that Hsp70/Hsc70 bind the intrinsically disordered amino-terminal region of SIMPL to stabilize the protein and thereby regulate its activity. Understanding the regulation of SIMPL through its interaction with Hsp70/Hsc70 may serve as a novel means of modulating tumor necrosis factor alpha signaling.

Original languageEnglish (US)
Pages (from-to)704-714
Number of pages11
JournalDNA and Cell Biology
Issue number12
StatePublished - Dec 1 2006


ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cell Biology

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