Kinesin-1 promotes centrosome clustering and nuclear migration in theDrosophilaoocyte

Abstract

Accurate positioning of the nucleus is essential in many cellular contexts. Microtubules and their associated motors are important players in this process. Although nuclear migration in Drosophila oocytes is controlled by microtubule-generated forces, a role for microtubule-associated molecular motors in nuclear positioning has yet to be reported. In this study, we first characterize novel landmarks that allow a precise description of the pre-migratory stages. Using these newly defined stages, we report that, prior to migration, the nucleus moves from the anterior side of the oocyte toward the center and concomitantly the centrosomes cluster at the posterior of the nucleus. In absence of Kinesin-1, centrosome clustering is impaired and the nucleus fails to position and migrate properly. In addition, we show that maintaining a high level of Polo-kinase at centrosomes prevents centrosome clustering and impairs nuclear positioning, suggesting that Kinesin-1 associated defects result from a failure to reduce centrosome activity. Consistently, depleting centrosomes rescues the nuclear migration defects induced by Kinesin-1 inactivation. In summary, our results suggest that Kinesin-1 controls nuclear migration in the oocyte by modulating centrosome activity.

Pericentrin interacts with Kinesin-1 to drive centriole motility

“…Indeed, work in C.elegans showed that Kinesin-1 was important to prevent the precocious activation of the sperm centriole during female Meiosis ( McNally et al, 2012 ). Kinesin-1 is also important for centrosome clustering in the Drosophila oocyte, a phenotype that could be mimicked by the artificial activation of Polo at the centrosome ( Loh et al, 2022 Preprint ).…”