Cdk1 promotes cytokinesis in fission yeast through activation of the septation initiation network
Autor: | Jun-Song Chen, Nicole Rachfall, Sapna Mehta, Kathleen L. Gould, Alyssa E. Johnson |
---|---|
Jazyk: | angličtina |
Rok vydání: | 2014 |
Předmět: |
Cell division
Cell Cycle Proteins Protein Serine-Threonine Kinases environment and public health Spindle pole body CDC2 Protein Kinase Schizosaccharomyces Phosphorylation Molecular Biology Mitosis Metaphase Cytokinesis Cyclin-dependent kinase 1 biology Cell Cycle Cell Biology Articles biology.organism_classification Cell biology Repressor Proteins enzymes and coenzymes (carbohydrates) Spindle Pole Bodies Schizosaccharomyces pombe Schizosaccharomyces pombe Proteins biological phenomena cell phenomena and immunity Protein Processing Post-Translational Signal Transduction |
Zdroj: | Molecular Biology of the Cell |
ISSN: | 1939-4586 1059-1524 |
Popis: | Although Cdk1 inhibits cytokinesis, it is shown that Cdk1 promotes an initial step by phosphorylating and promoting Byr4 removal from spindle pole bodies in metaphase. Because Byr4 inhibits the septation initiation network (SIN), Cdk1 helps prime the onset of cytokinesis by promoting the development of SIN asymmetry in concert with Plo1 kinase. In Schizosaccharomyces pombe, late mitotic events are coordinated with cytokinesis by the septation initiation network (SIN), an essential spindle pole body (SPB)–associated kinase cascade, which controls the formation, maintenance, and constriction of the cytokinetic ring. It is not fully understood how SIN initiation is temporally regulated, but it depends on the activation of the GTPase Spg1, which is inhibited during interphase by the essential bipartite GTPase-activating protein Byr4-Cdc16. Cells are particularly sensitive to the modulation of Byr4, which undergoes cell cycle–dependent phosphorylation presumed to regulate its function. Polo-like kinase, which promotes SIN activation, is partially responsible for Byr4 phosphorylation. Here we show that Byr4 is also controlled by cyclin-dependent kinase (Cdk1)–mediated phosphorylation. A Cdk1 nonphosphorylatable Byr4 phosphomutant displays severe cell division defects, including the formation of elongated, multinucleate cells, failure to maintain the cytokinetic ring, and compromised SPB association of the SIN kinase Cdc7. Our analyses show that Cdk1-mediated phosphoregulation of Byr4 facilitates complete removal of Byr4 from metaphase SPBs in concert with Plo1, revealing an unexpected role for Cdk1 in promoting cytokinesis through activation of the SIN pathway. |
Databáze: | OpenAIRE |
Externí odkaz: |