Proper timing of cytokinesis is regulated by Schizosaccharomyces pombe Etd1
UMass Chan Affiliations
Department of Molecular Genetics and MicrobiologyDocument Type
Journal ArticlePublication Date
2009-09-09Keywords
AnaphaseCell Cycle Proteins
Cytokinesis
Enzyme Activation
GTP Phosphohydrolases
Gene Knockdown Techniques
Guanine Nucleotide Exchange Factors
Mitotic Spindle Apparatus
Phenotype
Protein-Serine-Threonine KinasesRecombinant Fusion ProteinsSaccharomyces cerevisiae Proteins*SchizosaccharomycesSchizosaccharomyces pombe ProteinsSignal TransductionLife SciencesMedicine and Health Sciences
Metadata
Show full item recordAbstract
Cytokinesis must be initiated only after chromosomes have been segregated in anaphase and must be terminated once cleavage is completed. We show that the fission yeast protein Etd1 plays a central role in both of these processes. Etd1 activates the guanosine triphosphatase (GTPase) Spg1 to trigger signaling through the septum initiation network (SIN) pathway and onset of cytokinesis. Spg1 is activated in late anaphase when spindle elongation brings spindle pole body (SPB)-localized Spg1 into proximity with its activator Etd1 at cell tips, ensuring that cytokinesis is only initiated when the spindle is fully elongated. Spg1 is active at just one of the two SPBs during cytokinesis. When the actomyosin ring finishes constriction, the SIN triggers disappearance of Etd1 from the half of the cell with active Spg1, which then triggers Spg1 inactivation. Asymmetric activation of Spg1 is crucial for timely inactivation of the SIN. Together, these results suggest a mechanism whereby cell asymmetry is used to monitor cytoplasmic partitioning to turn off cytokinesis signaling.Source
J Cell Biol. 2009 Sep 7;186(5):739-53. Link to article on publisher's site
DOI
10.1083/jcb.200902116Permanent Link to this Item
http://hdl.handle.net/20.500.14038/39349PubMed ID
19736319Related Resources
Rights
© 2009 García-Cortés and McCollum This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.jcb.org/misc/terms.shtml). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).Distribution License
http://creativecommons.org/licenses/by-nc-sa/3.0/Scopus Count
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Except where otherwise noted, this item's license is described as © 2009 García-Cortés and McCollum This article is distributed under the terms of an
Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months
after the publication date (see http://www.jcb.org/misc/terms.shtml). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0
Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).
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