Abstract
Cytokinesis, which enables the physical separation of daughter cells once mitosis has been completed, is executed in fungal and animal cells by a contractile actin- and myosin-based ring (CAR). In the fission yeast Schizosaccharomyces pombe, the formin For3 nucleates actin cables and also co-operates for CAR assembly during cytokinesis. Mitogen-activated protein kinases (MAPKs) regulate essential adaptive responses in eukaryotic organisms to environmental changes. We show that the stress-activated protein kinase pathway (SAPK) and its effector, MAPK Sty1, downregulates CAR assembly in S. pombe when its integrity becomes compromised during cytoskeletal damage and stress by reducing For3 levels. Accurate control of For3 levels by the SAPK pathway may thus represent a novel regulatory mechanism of cytokinesis outcome in response to environmental cues. Conversely, SAPK signaling favors CAR assembly and integrity in its close relative Schizosaccharomyces japonicus, revealing a remarkable evolutionary divergence of this response within the fission yeast clade.
Highlights
Accurate cell division in eukaryotes requires the physical separation of daughter cells once mitosis has been completed
Among its numerous essential functions, Mitogen-activated protein kinases (MAPKs) participate in the dynamic remodeling of the actin cytoskeleton in eukaryotic organisms, and generally play a positive role reinforcing the actin-based structures, including the contractile actin- and myosin-based ring (CAR) (Pullikuth and Catling, 2007)
As opposed to this shared vision, we show in this work that fission yeast activation of the stress-activated protein kinase pathway (SAPK) Sty1, a p38 MAPK ortholog, negatively regulates CAR assembly and integrity in response to actin polymerization inhibition induced with Latrunculin A (LatA)
Summary
Accurate cell division in eukaryotes requires the physical separation of daughter cells once mitosis has been completed. The rod-shaped fission yeast Schizosaccharomyces pombe is a popular model organism for the study of cytokinesis due to its small size, a relatively simple actin-based cytoskeletal network (actin patches, actin cables, and the CAR), and an tractable small genome with little gene redundancy (Rincon and Paoletti, 2016; Balasubramanian et al, 2004). These features have allowed the identification of a large number of evolutionary conserved cytokinesis proteins and the precise spatiotemporal analysis of cytokinetic events (Pollard and Wu, 2010). Once the nuclear division is completed, the CAR constricts and drives plasma
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
