8YY3

Kinesin-14 in nucleotide-free state bound to 14 PF Microtubule

Summary for 8YY3

• Entry DOI: 10.2210/pdb8yy3/pdb
• EMDB information: 39665
• Descriptor: Tubulin alpha-1B chain, Tubulin beta chain, Protein claret segregational, ... (7 entities in total)
• Functional Keywords: kinesin motor proteins, force production, power stroke fluctuations, motor spring-like element, reversed motility, mechanochemical coupling, mechanical states, cell cycle
• Biological source: Drosophila melanogaster (fruit fly); More
• Total number of polymer chains: 4
• Total formula weight: 194240.87

Authors

Shibata, S.,Imasaki, T.,Shigematsu, H.,Endow, S.A.,Nitta, R. (deposition date: 2024-04-03, release date: 2025-10-08, Last modification date: 2025-10-22)

Primary citation

Shibata, S.,Wang, M.Y.,Imasaki, T.,Shigematsu, H.,Wei, Y.,Jobichen, C.,Hagio, H.,Sivaraman, J.,Endow, S.A.,Nitta, R.
Structural transitions in kinesin minus-end directed microtubule motility.
Biorxiv, 2024

PubMed Abstract: Kinesin motor proteins hydrolyze ATP to produce force for spindle assembly and vesicle transport, performing essential functions in cell division and motility, but the structural changes required for force generation are uncertain. We now report high-resolution structures showing new transitions in the kinesin mechanochemical cycle, including power stroke fluctuations upon ATP binding and a post-hydrolysis state with bound ADP + free phosphate. We find that rate-limiting ADP release occurs upon microtubule binding, accompanied by central β-sheet twisting, which triggers the power stroke - stalk rotation and neck mimic docking - upon ATP binding. Microtubule release occurs with β-strand-to-loop transitions, implying that β-strand refolding induces Pi release and the recovery stroke. The strained β-sheet during the power stroke and strand-to-loop transitions identify the β-sheet as the long-sought motor spring.

PubMed: 39131399
DOI: 10.1101/2024.07.29.605428

Experimental method

ELECTRON MICROSCOPY (3.24 Å)