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bioRxiv · 10.1101/2024.11.26.625568

Structural and functional insights into activation and regulation of the dynein-dynactin-NuMA complex

Aslan, M.·Cho, N. H.·d'Amico, E. A.·Taheri, A.·Zhao, Y.·Zhong, X.·Blaauw, M.·Carter, A. P.·Dumont, S.·Yildiz, A.
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Abstract

During cell division, NuMA orchestrates the focusing of microtubule minus-ends in spindle poles and cortical force generation on astral microtubules by interacting with dynein motors, microtubules, and other cellular factors. Here, we used in vitro reconstitution, cryo-electron microscopy, and live cell imaging to understand the mechanism and regulation of NuMA. We determined the structure of the processive dynein/dynactin/NuMA complex (DDN) and showed that the NuMA N-terminus drives dynein motility in vitro and facilitates dynein-mediated transport in live cells. The C-terminus of NuMA directly binds to and suppresses the dynamics of the microtubule minus-end. Full-length NuMA is autoinhibited for its interactions with dynein and microtubules, but mitotically phosphorylated NuMA activates dynein in vitro and interphase cells. Together with dynein, activated full-length NuMA focuses microtubule minus-ends into aster-like structures. These results provide critical insights into the activation of NuMA and dynein for their mitotic functions.

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Aslan, M., Cho, N. H., d'Amico, E. A., Taheri, A., Zhao, Y., Zhong, X., Blaauw, M., Carter, A. P., Dumont, S., Yildiz, A.. 2024-11-29. Structural and functional insights into activation and regulation of the dynein-dynactin-NuMA complex. https://doi.org/10.1101/2024.11.26.625568

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