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bioRxiv · 10.1101/183160

Cryo-EM shows how dynactin recruits two dyneins for faster movement

Urnavicius, L.·Lau, C. K.·Elshenawy, M. M.·Morales-Rios, E.·Motz, C.·Yildiz, A.·Carter, A. P.
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Abstract

Dynein and its cofactor dynactin form a highly processive microtubule motor in the presence of an activating adaptor, such as BICD2. Different adaptors link dynein/dynactin to distinct cargos. Here we use electron microscopy (EM) and single molecule studies to show that adaptors can recruit a second dynein to dynactin. Whereas BICD2 is biased toward recruiting a single dynein, the adaptors BICDR1 and HOOK3 predominantly recruit two. We find that the shift toward a double dynein complex increases both force and speed. A 3.5 [A] cryo-EM reconstruction of a dynein tail/dynactin/BICDR1 complex reveals how dynactin can act as a scaffold to coordinate two dyneins side by side. Our work provides a structural basis for how diverse adaptors recruit different numbers of dyneins and regulate the motile properties of the dynein/dynactin transport machine.

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Urnavicius, L., Lau, C. K., Elshenawy, M. M., Morales-Rios, E., Motz, C., Yildiz, A., Carter, A. P.. 2017-08-31. Cryo-EM shows how dynactin recruits two dyneins for faster movement. https://doi.org/10.1101/183160

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