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bioRxiv · 10.1101/083618

CENP-F couples cargo to growing and shortening microtubule ends

Kanfer, G.·Peterka, M.·Arzhanik, V. K.·Drobyshev, A. L.·Ataullakhanov, F. I.·Volkov, V. A.·Kornmann, B.
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Abstract

Dynamic microtubule ends exert pulling and pushing forces on intracellular membranes and organelles. However, the mechanical linkage of microtubule tips to their cargoes is poorly understood. CENP-F is a non-motor microtubule-binding protein that participates in microtubule binding at kinetochores and in the mitotic redistribution of the mitochondrial network. CENP-F-driven mitochondrial transport is linked to growing microtubule tips, but the underlying molecular mechanisms are unknown. Here we show that CENP-F tracks growing microtubule ends in living cells. In vitro reconstitution demonstrates that microtubule tips can transport mitochondria and CENP-F-coated artificial cargoes over micrometer-long distances, during both growing and shrinking phases. Based on these and previous observations, we suggest that CENP-F might act as a transporter of mitochondria and other cellular cargoes by attaching them to dynamic microtubule ends.

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Kanfer, G., Peterka, M., Arzhanik, V. K., Drobyshev, A. L., Ataullakhanov, F. I., Volkov, V. A., Kornmann, B.. 2016-10-26. CENP-F couples cargo to growing and shortening microtubule ends. https://doi.org/10.1101/083618

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