Programmed Variations of Cytokinesis Contribute to Morphogenesis in the C. elegans embryo

Bai, X.; Lee, P.-Y.; Chen, C.-Y.; Simmons, J. R.; Nebenfuehr, B.; Mitchell, D.; Klebanow, L. R.; Mattson, N.; Turpin, C.; Chen, B.-C.; Betzig, E.; Bembenek, J. N.

doi:10.1101/319657

bioRxiv · 10.1101/319657

Programmed Variations of Cytokinesis Contribute to Morphogenesis in the C. elegans embryo

Bai, X.·Lee, P.-Y.·Chen, C.-Y.·Simmons, J. R.·Nebenfuehr, B.·Mitchell, D.·Klebanow, L. R.·Mattson, N.·Turpin, C.·Chen, B.-C.·Betzig, E.·Bembenek, J. N.

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Abstract

While cytokinesis has been intensely studied, how it is executed during development is not well understood, despite a long-standing appreciation that various aspects of cytokinesis vary across cell and tissue types. To address this, we investigated cytokinesis during the invariant C. elegans embryo lineage and found several reproducibly altered parameters at different stages. During early divisions, furrow ingression asymmetry and midbody inheritance is consistent, suggesting specific regulation of these events. During morphogenesis, we find several unexpected alterations including migration of midbodies to the apical surface during epithelial polarization in different tissues. Aurora B kinase, which is essential for several aspects of cytokinesis, remains localized to the apical membrane after internalization of other midbody components. Inactivation of Aurora B causes cytokinesis failure, which disrupts polarization and tissue formation. Therefore, cytokinesis shows surprising diversity during development and is required during epithelial polarization to establish cellular architecture during morphogenesis.

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Bai, X., Lee, P.-Y., Chen, C.-Y., Simmons, J. R., Nebenfuehr, B., Mitchell, D., Klebanow, L. R., Mattson, N., Turpin, C., Chen, B.-C., Betzig, E., Bembenek, J. N.. 2018-05-10. Programmed Variations of Cytokinesis Contribute to Morphogenesis in the C. elegans embryo. https://doi.org/10.1101/319657

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