First Author | Valiyaveettil M | Year | 2008 |
Journal | J Cell Biol | Volume | 182 |
Issue | 4 | Pages | 727-39 |
PubMed ID | 18710924 | Mgi Jnum | J:138977 |
Mgi Id | MGI:3806927 | Doi | 10.1083/jcb.200801133 |
Citation | Valiyaveettil M, et al. (2008) Novel role of the muskelin-RanBP9 complex as a nucleocytoplasmic mediator of cell morphology regulation. J Cell Biol 182(4):727-39 |
abstractText | The evolutionarily conserved kelch-repeat protein muskelin was identified as an intracellular mediator of cell spreading. We discovered that its morphological activity is controlled by association with RanBP9/RanBPM, a protein involved in transmembrane signaling and a conserved intracellular protein complex. By subcellular fractionation, endogenous muskelin is present in both the nucleus and the cytosol. Muskelin subcellular localization is coregulated by its C terminus, which provides a cytoplasmic restraint and also controls the interaction of muskelin with RanBP9, and its atypical lissencephaly-1 homology motif, which has a nuclear localization activity which is regulated by the status of the C terminus. Transient or stable short interfering RNA-based knockdown of muskelin resulted in protrusive cell morphologies with enlarged cell perimeters. Morphology was specifically restored by complementary DNAs encoding forms of muskelin with full activity of the C terminus for cytoplasmic localization and RanBP9 binding. Knockdown of RanBP9 resulted in equivalent morphological alterations. These novel findings identify a role for muskelin-RanBP9 complex in pathways that integrate cell morphology regulation and nucleocytoplasmic communication. |