Proper timing of cytokinesis is regulated by Schizosaccharomyces pombe Etd1
UMass Chan AffiliationsDepartment of Molecular Genetics and Microbiology
Document TypeJournal Article
Cell Cycle Proteins
Gene Knockdown Techniques
Guanine Nucleotide Exchange Factors
Mitotic Spindle Apparatus
Recombinant Fusion Proteins
Saccharomyces cerevisiae Proteins
Schizosaccharomyces pombe Proteins
Medicine and Health Sciences
MetadataShow full item record
AbstractCytokinesis 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.
J Cell Biol. 2009 Sep 7;186(5):739-53. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/39349
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/).
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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