A disassembly-driven mechanism explains F-actin-mediated chromosome transport in starfish oocytes

eLife

Serge Dmitrieff¹  François J Nédélec¹  Julio M Belmonte¹  Philippe Bun¹  Péter Lénárt¹ 

[1] Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany;

关键词: oocyte meiosis;    actin dynamics;    contractility;    Patiria miniata;    cytoskeleton;    cell division;   

DOI  :  10.7554/eLife.31469

来源: DOAJ

【 摘 要 】

While contraction of sarcomeric actomyosin assemblies is well understood, this is not the case for disordered networks of actin filaments (F-actin) driving diverse essential processes in animal cells. For example, at the onset of meiosis in starfish oocytes a contractile F-actin network forms in the nuclear region transporting embedded chromosomes to the assembling microtubule spindle. Here, we addressed the mechanism driving contraction of this 3D disordered F-actin network by comparing quantitative observations to computational models. We analyzed 3D chromosome trajectories and imaged filament dynamics to monitor network behavior under various physical and chemical perturbations. We found no evidence of myosin activity driving network contractility. Instead, our observations are well explained by models based on a disassembly-driven contractile mechanism. We reconstitute this disassembly-based contractile system in silico revealing a simple architecture that robustly drives chromosome transport to prevent aneuploidy in the large oocyte, a prerequisite for normal embryonic development.

【 授权许可】

Unknown