Dissecting the Role of Rho-mediated Signaling in Contractile Ring Formation
| Autor: | Keiju Kamijo, Jae Seon Lee, Hiroshi Hosoya, Takashi Uchimura, Toru Miki, Mitsuhiro Abe, Naoya Ohara |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
rho GTP-Binding Proteins
Cleavage furrow formation Spindle Apparatus Myosins Biology Microtubules Humans Central spindle Molecular Biology Actin Cytokinesis Articles Cell Biology Centralspindlin complex Actins rac GTP-Binding Proteins Spindle apparatus Cell biology Rac GTP-Binding Proteins Protein Transport Gene Expression Regulation Centralspindlin RNA Interference Microtubule-Associated Proteins HeLa Cells Protein Binding Signal Transduction |
| Zdroj: | Molecular Biology of the Cell. 17:43-55 |
| ISSN: | 1939-4586 1059-1524 |
| DOI: | 10.1091/mbc.e05-06-0569 |
| Popis: | In anaphase, microtubules provide a specification signal for positioning of the contractile ring. However, the nature of the signal remains unknown. The small GTPase Rho is a potent regulator of cytokinesis, but the involvement of Rho in contractile ring formation is disputed. Here, we show that Rho serves as a microtubule-dependent signal that specifies the position of the contractile ring. We found that Rho translocates to the equatorial region before furrow ingression. The Rho-specific inhibitor C3 exoenzyme and small interfering RNA to the Rho GDP/GTP exchange factor ECT2 prevent this translocation and disrupt contractile ring formation, indicating that active Rho is required for contractile ring formation. ECT2 forms a complex with the GTPase-activating protein MgcRacGAP and the kinesinlike protein MKLP1 at the central spindle, and the localization of ECT2 at the central spindle depends on MgcRacGAP and MKLP1. In addition, we show that the bundled microtubules direct Rho-mediated signaling molecules to the furrowing site and regulate furrow formation. Our study provides strong evidence for the requirement of Rho-mediated signaling in contractile ring formation. |
| Databáze: | OpenAIRE |
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