First Author | Lukic Z | Year | 2011 |
Journal | Retrovirology | Volume | 8 |
Pages | 93 | PubMed ID | 22078707 |
Mgi Jnum | J:196249 | Mgi Id | MGI:5487513 |
Doi | 10.1186/1742-4690-8-93 | Citation | Lukic Z, et al. (2011) TRIM5alpha associates with proteasomal subunits in cells while in complex with HIV-1 virions. Retrovirology 8:93 |
abstractText | BACKGROUND: The TRIM5 proteins are cellular restriction factors that prevent retroviral infection in a species-specific manner. Multiple experiments indicate that restriction activity requires accessory host factors, including E2-enzymes. To better understand the mechanism of restriction, we conducted yeast-two hybrid screens to identify proteins that bind to two TRIM5 orthologues. RESULTS: The only cDNAs that scored on repeat testing with both TRIM5 orthologues were the proteasome subunit PSMC2 and ubiquitin. Using co-immunoprecipitation assays, we demonstrated an interaction between TRIM5alpha and PSMC2, as well as numerous other proteasome subunits. Fluorescence microscopy revealed co-localization of proteasomes and TRIM5alpha cytoplasmic bodies. Forster resonance energy transfer (FRET) analysis indicated that the interaction between TRIM5 and PSMC2 was direct. Previous imaging experiments demonstrated that, when cells are challenged with fluorescently-labeled HIV-1 virions, restrictive TRIM5alpha orthologues assemble cytoplasmic bodies around incoming virion particles. Following virus challenge, we observed localization of proteasome subunits to rhTRIM5alpha cytoplasmic bodies that contained fluorescently labeled HIV-1 virions. CONCLUSIONS: Taken together, the results presented here suggest that localization of the proteasome to TRIM5alpha cytoplasmic bodies makes an important contribution to TRIM5alpha-mediated restriction. |