Actin dynamics in the contractile ring during cytokinesis in fission yeast

@article{Pelham2002ActinDI,
  title={Actin dynamics in the contractile ring during cytokinesis in fission yeast},
  author={Robert J. Pelham and Fred Chang},
  journal={Nature},
  year={2002},
  volume={419},
  pages={82-86}
}
Cytokinesis in many eukaryotes requires a contractile ring of actin and myosin that cleaves the cell in two. Little is known about how actin filaments and other components assemble into this ring structure and generate force. Here we show that the contractile ring in the fission yeast Schizosaccharomyces pombe is an active site of actin assembly. This actin polymerization activity requires Arp3, the formin Cdc12, profilin and WASP, but not myosin II or IQGAP proteins. Both newly polymerized… 

Contractile‐ring assembly in fission yeast cytokinesis: Recent advances and new perspectives

The fission yeast Schizosaccharomyces pombe is an excellent model organism to study cytokinesis and the assembly of cytokine nodes, the precursors of a normal contractile ring, is summarized and possible mechanisms underlying the ring maturation and constriction are discussed.

Roles of formin nodes and myosin motor activity in Mid1p-dependent contractile-ring assembly during fission yeast cytokinesis.

Live microscopy of cells expressing Cdc12p fluorescent fusion proteins shows for the first time that CDC12p localizes to a broad band of 30-50 dynamic nodes, where actin filaments are nucleated in random directions, providing strong support for the SCPR model of contractile-ring formation in cytokinesis.

Role of tropomyosin in formin-mediated contractile ring assembly in fission yeast.

It is discovered that Cdc12p can recruit SpTm to actin filaments and that SpTtm has diverse effects on CDC12p-mediated actin assembly, and makes multiple contributions to contractile ring assembly during and after actin polymerization.

Actin turnover maintains actin filament homeostasis during cytokinetic ring contraction

It is concluded that actin turnover is required to maintain actin filamentHomeostasis during ring contraction and that the requirement for turnover can be bypassed if homeostasis is achieved artificially.

Formins filter modified actin subunits during processive elongation.

Assembly of the cytokinetic contractile ring from a broad band of nodes in fission yeast

We observed live fission yeast expressing pairs of functional fluorescent fusion proteins to test the popular model that the cytokinetic contractile ring assembles from a single myosin II progenitor

Actin turnover protects the cytokinetic contractile ring from structural instability

Molecularly explicit simulations showed that cofilin-mediated actin severing protects the fission yeast cytokinetic contractile ring from instabilities in which actin peels away from the plasma membrane into straight bridges.

The fission yeast cytokinesis formin Cdc12p is a barbed end actin filament capping protein gated by profilin

Formins are profilin-gated barbed end capping proteins with the ability to initiate actin filaments from actin monomers bound toProfilins that bind both actin and poly-l-proline inhibit nucleation by Cdc12(FH1FH2)p, but polymerization of monomeric actin is faster, because the filaments grow from their barbed ends at the same rate as uncapped filaments.

Myosin-II-Dependent Localization and Dynamics of F-Actin during Cytokinesis

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