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bioRxiv · 10.1101/2021.11.19.469242

Cortical microtubule pulling forces contribute to the union of the parental genomes in the C. elegans zygote

VELEZ-AGUILERA, G.·OSSAREH-NAZARI, B.·VAN HOVE, L.·Joly, N.·Pintard, L.
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Abstract

Previously, we reported that the Polo-like kinase PLK-1 phosphorylates the single C. elegans lamin (LMN-1) to trigger lamina depolymerization during mitosis. We showed that this event is required for the formation of a pronuclear envelopes scission event that removes membranes on the juxtaposed oocyte and sperm pronuclear envelopes in the zygote, allowing the parental chromosomes to merge in a single nucleus after segregation (Velez-Aguilera, 2020). Here we show that cortical microtubule pulling forces contribute to pronuclear envelopes scission by promoting mitotic spindle elongation. We also demonstrate that weakening of the pronuclear envelopes, via PLK-1-mediated lamina depolymerization, is a prerequisite for the astral microtubule pulling forces to trigger pronuclear membranes scission. Finally, we provide evidence that PLK-1 mainly acts via lamina depolymerization in this process. These observations thus indicate that temporal coordination between lamina depolymerization and mitotic spindle elongation facilitates pronuclear envelopes scission and parental genomes unification.

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VELEZ-AGUILERA, G., OSSAREH-NAZARI, B., VAN HOVE, L., Joly, N., Pintard, L.. 2021-11-19. Cortical microtubule pulling forces contribute to the union of the parental genomes in the C. elegans zygote. https://doi.org/10.1101/2021.11.19.469242

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