biostudies-literatureBouvrais HEuropean Molecular Biology OrganizationLigue Contre le CancerCentre National de la Recherche ScientifiqueEuropean Cooperation in Science and TechnologyNIH HHSe50770https://www.ebi.ac.uk/biostudies/studies/S-EPMC8097383biostudies-literatureUnknown22(5)In Caenorhabditis elegans zygote, astral microtubules generate forces essential to position the mitotic spindle, by pushing against and pulling from the cortex. Measuring microtubule dynamics there, we revealed the presence of two populations, corresponding to pulling and pushing events. It offers a unique opportunity to study, under physiological conditions, the variations of both spindle-positioning forces along space and time. We propose a threefold control of pulling force, by polarity, spindle position and mitotic progression. We showed that the sole anteroposterior asymmetry in dynein on-rate, encoding pulling force imbalance, is sufficient to cause posterior spindle displacement. The positional regulation, reflecting the number of microtubule contacts in the posterior-most region, rEMBO reportsThe coordination of spindle-positioning forces during the asymmetric division of the Caenorhabditis elegans zygote.PMC8097383ATIPBM1408 (GENiE)P40 OD010440ALTF 326‐2013Chesneau LPastezeur SPecot TLe Cunff YPecreaux JBouvrais HSoler NKervrann CFairbrass DfalseThe coordination of spindle-positioning forces during the asymmetric division of the Caenorhabditis elegans zygote.In Caenorhabditis elegans zygote, astral microtubules generate forces essential to position the mitotic spindle, by pushing against and pulling from the cortex. Measuring microtubule dynamics there, we revealed the presence of two populations, corresponding to pulling and pushing events. It offers a unique opportunity to study, under physiological conditions, the variations of both spindle-positioning forces along space and time. We propose a threefold control of pulling force, by polarity, spindle position and mitotic progression. We showed that the sole anteroposterior asymmetry in dynein on-rate, encoding pulling force imbalance, is sufficient to cause posterior spindle displacement. The positional regulation, reflecting the number of microtubule contacts in the posterior-most region, r2021-01-01T00:00:00Z2021 May2025-04-05T14:05:26.484Z2025-04-05T14:05:26.484ZS-EPMC80973833390001510.15252/embr.202050770