Myosin II regulatory light chain phosphorylation and formin availability modulate cytokinesis upon changes in carbohydrate metabolism
- Universidad de Murcia, Spain
- Universidad de Salamanca, Spain
Abstract
Cytokinesis, the separation of daughter cells at the end of mitosis, relies in animal cells on a contractile actomyosin ring (CAR) composed of actin and class II myosins, whose activity is strongly influenced by regulatory light chain (RLC) phosphorylation. However, in simple eukaryotes such as the fission yeast Schizosaccharomyces pombe, RLC phosphorylation appears dispensable for regulating CAR dynamics. We found that redundant phosphorylation at Ser35 of the S. pombe RLC homolog Rlc1 by the p21-activated kinases Pak1 and Pak2, modulates myosin II Myo2 activity and becomes essential for cytokinesis and cell growth during respiration. Previously, we showed that the stress activated protein kinase pathway (SAPK) MAPK Sty1 controls fission yeast CAR integrity by downregulating formin For3 levels (Gomez-Gil et al.,2020). Here, we report that the reduced availability of formin For3-nucleated actin filaments for the CAR is the main reason for the required control of myosin II contractile activity by RLC phosphorylation during respiration-induced oxidative stress. Thus, the restoration of For3 levels by antioxidants overrides the control of myosin II function regulated by RLC phosphorylation, allowing cytokinesis and cell proliferation during respiration. Therefore, fine-tuned interplay between myosin II function through Rlc1 phosphorylation and environmentally controlled actin filament availability is critical for a successful cytokinesis in response to a switch to a respiratory carbohydrate metabolism.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Armando Jesus Perez-Diaz
Jero Vicente-Soler
Funding
Agencia Estatal de Investigación (PID2020-112569GB-I00)
- Jose Cansado
Agencia Estatal de Investigación (PGC2018-098924-B-I00)
- Pilar Pérez
Regional Government of Castile and Leon (CSI150P20)
- Pilar Pérez
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Prieto-Ruiz 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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Myosin II regulatory light chain phosphorylation and formin availability modulate cytokinesis upon changes in carbohydrate metabolism
eLife 12:e83285.
https://doi.org/10.7554/eLife.83285
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