Interaction of heat-shock protein 90β isoform (HSP90β) with cellular inhibitor of apoptosis 1 (c-IAP1) is required for cell differentiation Journal Article
| Authors: | Didelot, C.; Lanneau, D.; Brunet, M.; Bouchot, A.; Cartier, J.; Jacquel, A.; Ducoroy, P.; Cathelin, S.; Decologne, N.; Chiosis, G.; Dubrez-Daloz, L.; Solary, E.; Garrido, C. |
| Article Title: | Interaction of heat-shock protein 90β isoform (HSP90β) with cellular inhibitor of apoptosis 1 (c-IAP1) is required for cell differentiation |
| Abstract: | Members of the inhibitor of apoptosis protein (IAP) family have demonstrated functions in cell death, cell signalling, cell migration and mitosis. Several of them are E3 enzymes in the ubiquitination of proteins that leads to their degradation by the proteosomal machinery. We previously reported that one of them, cellular inhibitor of apoptosis protein-1 (c-IAP1), migrated from the nucleus to the surface of the Golgi apparatus in cells undergoing differentiation. Here, we show that c-IAP1 is a client protein of the stress protein HSP90β. In three distinct cellular models, the two proteins interact and migrate from the nucleus to the cytoplasm along the differentiation process through a leptomycin B-sensitive pathway. Inhibition of HSP90 proteins by small chemical molecules and specific depletion of HSP90β isoform by siRNA both lead to auto-ubiquitination of c-IAP1 and its degradation by the proteasome machinery. This chaperone function of HSP90 towards c-IAP1 is specific of its β isoform as specific depletion of HSP90α does not affect c-IAP1 content. Chemical inhibition of HSP90 or siRNA-mediated depletion of HSP90β both inhibit cell differentiation, which can be reproduced by siRNA-mediated depletion of c-IAP1. Altogether, these results suggest that HSP90β prevents auto-ubiquitination and degradation of its client protein c-IAP1, whose depletion would be sufficient to inhibit cell differentiation. |
| Keywords: | controlled study; unclassified drug; human cell; protein function; protein localization; animals; proteasome; protein degradation; protein depletion; protein protein interaction; small interfering rna; rna, small interfering; cell differentiation; cell line, tumor; ubiquitination; inhibitor of apoptosis protein 1; inhibitor of apoptosis proteins; protein transport; epithelial cells; heat shock protein 90; hsp90 heat-shock proteins; cellular distribution; cytoplasm; cell nucleus; macrophages; isoprotein; protein isoforms; molecular model; growth inhibition; chaperone; leptomycin b; heat shock protein 90beta |
| Journal Title: | Cell Death and Differentiation |
| Volume: | 15 |
| Issue: | 5 |
| ISSN: | 1350-9047 |
| Publisher: | Nature Publishing Group |
| Date Published: | 2008-05-01 |
| Start Page: | 859 |
| End Page: | 866 |
| Language: | English |
| DOI: | 10.1038/cdd.2008.5 |
| PUBMED: | 18239673 |
| PROVIDER: | scopus |
| DOI/URL: | |
| Notes: | --- - "Cited By (since 1996): 9" - "Export Date: 17 November 2011" - "CODEN: CDDIE" - "Source: Scopus" |
