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Confinement induces actin flow in a meiotic cytoplasm.

ABSTRACT: In vivo, F-actin flows are observed at different cell life stages and participate in various developmental processes during asymmetric divisions in vertebrate oocytes, cell migration, or wound healing. Here, we show that confinement has a dramatic effect on F-actin spatiotemporal organization. We reconstitute in vitro the spontaneous generation of F-actin flow using Xenopus meiotic extracts artificially confined within a geometry mimicking the cell boundary. Perturbations of actin polymerization kinetics or F-actin nucleation sites strongly modify the network flow dynamics. A combination of quantitative image analysis and biochemical perturbations shows that both spatial localization of F-actin nucleators and actin turnover play a decisive role in generating flow. Interestingly, our in vitro assay recapitulates several symmetry-breaking processes observed in oocytes and early embryonic cells.

SUBMITTER: Pinot M

PROVIDER: S-EPMC3406835 | biostudies-other | 2012 Jul

REPOSITORIES: biostudies-other

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Confinement induces actin flow in a meiotic cytoplasm.

Pinot Mathieu M Steiner Villier V Dehapiot Benoit B Yoo Byung-Kuk BK Chesnel Franck F Blanchoin Laurent L Kervrann Charles C Gueroui Zoher Z

Proceedings of the National Academy of Sciences of the United States of America 20120702 29

In vivo, F-actin flows are observed at different cell life stages and participate in various developmental processes during asymmetric divisions in vertebrate oocytes, cell migration, or wound healing. Here, we show that confinement has a dramatic effect on F-actin spatiotemporal organization. We reconstitute in vitro the spontaneous generation of F-actin flow using Xenopus meiotic extracts artificially confined within a geometry mimicking the cell boundary. Perturbations of actin polymerization ...[more]

PMID: 22753521

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