First Author | Stauffer DR | Year | 2001 |
Journal | J Cell Sci | Volume | 114 |
Issue | Pt 13 | Pages | 2383-93 |
PubMed ID | 11559747 | Mgi Jnum | J:114049 |
Mgi Id | MGI:3688059 | Doi | 10.1242/jcs.114.13.2383 |
Citation | Stauffer DR, et al. (2001) CHMP1 is a novel nuclear matrix protein affecting chromatin structure and cell-cycle progression. J Cell Sci 114(Pt 13):2383-93 |
abstractText | The Polycomb-group (PcG) is a diverse set of proteins required for maintenance of gene silencing during development. In a screen for conserved partners of the PcG protein Polycomblike (Pcl), we have identified a new protein, human CHMP1 (CHromatin Modifying Protein; CHarged Multivesicular body Protein), which is encoded by an alternative open reading frame in the PRSM1 gene and is conserved in both complex and simple eukaryotes. CHMP1 contains a predicted bipartite nuclear localization signal and distributes as distinct forms to the cytoplasm and the nuclear matrix in all cell lines tested. We have constructed a stable HEK293 cell line that inducibly overexpresses CHMP1 under ecdysone control. Overexpressed CHMP1 localizes to a punctate subnuclear pattern, encapsulating regions of nuclease-resistant, condensed chromatin. These novel structures are also frequently surrounded by increased histone H3 phosphorylation and acetylation. CHMP1 can recruit a PcG protein, BMI1, to these regions of condensed chromatin and can cooperate with co-expressed vertebrate Pcl in a Xenopus embryo PcG assay; this is consistent with a role in PcG function. In combination, these observations suggest that CHMP1 plays a role in stable gene silencing within the nucleus. |