Stress-activated MAPK signalling controls fission yeast actomyosin ring integrity by modulating formin For3 levels
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 signalling favours CAR assembly and integrity in its close relative S. japonicus, revealing a remarkable evolutionary divergence of this response within the fission yeast clade.
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All data generated or analysed during this study are included within the manuscript and supporting files.
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Author details
Funding
Ministerio de Economía y Competitividad (BFU2017-82423-P)
- Jose Cansado
Ministerio de Economía y Competitividad (PGC2018-098924-B-100)
- Pilar Pérez
Junta de Castilla y Leon (CLU-2017-03)
- Pilar Pérez
Fundacion Seneca (20856/PI/18)
- Jose Cansado
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Gómez-Gil et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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