An Anillin-Ect2 Complex Stabilizes Central Spindle Microtubules at the Cortex during Cytokinesis
Open Access
- 13 April 2012
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 7 (4), e34888
- https://doi.org/10.1371/journal.pone.0034888
Abstract
Cytokinesis occurs due to the RhoA-dependent ingression of an actomyosin ring. During anaphase, the Rho GEF (guanine nucleotide exchange factor) Ect2 is recruited to the central spindle via its interaction with MgcRacGAP/Cyk-4, and activates RhoA in the central plane of the cell. Ect2 also localizes to the cortex, where it has access to RhoA. The N-terminus of Ect2 binds to Cyk-4, and the C-terminus contains conserved DH (Dbl homologous) and PH (Pleckstrin Homology) domains with GEF activity. The PH domain is required for Ect2's cortical localization, but its molecular function is not known. In cultured human cells, we found that the PH domain interacts with anillin, a contractile ring protein that scaffolds actin and myosin and interacts with RhoA. The anillin-Ect2 interaction may require Ect2's association with lipids, since a novel mutation in the PH domain, which disrupts phospholipid association, weakens their interaction. An anillin-RacGAP50C (homologue of Cyk-4) complex was previously described in Drosophila, which may crosslink the central spindle to the cortex to stabilize the position of the contractile ring. Our data supports an analogous function for the anillin-Ect2 complex in human cells and one hypothesis is that this complex has functionally replaced the Drosophila anillin-RacGAP50C complex. Complexes between central spindle proteins and cortical proteins could regulate the position of the contractile ring by stabilizing microtubule-cortical interactions at the division plane to ensure the generation of active RhoA in a discrete zone.Keywords
This publication has 46 references indexed in Scilit:
- Polar actomyosin contractility destabilizes the position of the cytokinetic furrowNature, 2011
- Stabilization of the Actomyosin Ring Enables Spermatocyte Cytokinesis in DrosophilaMolecular Biology of the Cell, 2010
- Analyzing the Effects of Delaying Aster Separation on Furrow Formation during Cytokinesis in the Caenorhabditis elegans EmbryoMolecular Biology of the Cell, 2010
- Action at a distance during cytokinesisThe Journal of cell biology, 2009
- Mechanisms for concentrating Rho1 during cytokinesisGenes & Development, 2009
- Regulation of the Rac GTPase pathway by the multifunctional Rho GEF Pebble is essential for mesoderm migration in theDrosophilagastrulaDevelopment, 2009
- Centrosome/Spindle Pole–associated Protein Regulates Cytokinesis via Promoting the Recruitment of MyoGEF to the Central SpindleMolecular Biology of the Cell, 2009
- Regulation of cytokinesis by Rho GTPase fluxNature, 2008
- Inhibition of Rac by the GAP Activity of Centralspindlin Is Essential for CytokinesisScience, 2008
- Rho-dependent control of anillin behavior during cytokinesisThe Journal of cell biology, 2008