Cryo-EM Reveals the Mechanochemical Cycle of Reactive Full-length Human Dynein-1

Chai, P.; Yang, J.; Geohring, I. C.; Markus, S. M.; Wang, Y.; Zhang, K.

doi:10.1101/2024.05.01.592044

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bioRxiv · 10.1101/2024.05.01.592044

Cryo-EM Reveals the Mechanochemical Cycle of Reactive Full-length Human Dynein-1

Chai, P.·Yang, J.·Geohring, I. C.·Markus, S. M.·Wang, Y.·Zhang, K.

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Abstract

Dynein-driven cargo transport plays pivotal roles in diverse cellular activities, central to which is dyneins mechanochemical cycle. Here, we performed a systematic cryo-electron microscopic investigation of the conformational landscape of full-length human dynein-1 in reaction, under various nucleotide conditions, on and off microtubules. Our approach reveals over 40 high-resolution structures, categorized into eight states, providing a dynamic and comprehensive view of dynein throughout its mechanochemical cycle. The novel intermediate states reveal important mechanistic insights into dynein function, including a backdoor phosphate release model that coordinates linker straightening, how microtubule binding enhances ATPase activity through a two-way communication mechanism, and the crosstalk mechanism between AAA1 and the regulatory AAA3 site. Our findings also lead to a substantially revised model for the force-generating powerstroke and reveal a means by which dynein exhibits unidirectional stepping. These results substantially improve our understanding of dynein and provide a more complete model of its mechanochemical cycle.

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Chai, P., Yang, J., Geohring, I. C., Markus, S. M., Wang, Y., Zhang, K.. 2024-05-01. Cryo-EM Reveals the Mechanochemical Cycle of Reactive Full-length Human Dynein-1. https://doi.org/10.1101/2024.05.01.592044

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