Biophysical Society Thematic Meeting | Hamburg 2022

Biophysics at the Dawn of Exascale Computers

Poster Abstracts

29-POS Board 29 POST-TRANSLATIONAL MODIFICATION OF MICROTUBULES CAN CONTROL DYNEIN-2'S ABILITY TO WALK ON A-TUBULES Shintaroh Kubo 1,2 ; Khanh Huy Bui 1 ; 1 McGill University, Anatomy and Cell Biology, Montreal, QC, Canada 2 University of Tokyo, Medicine, Bunkyo-ku, Japan The microtubules (MTs) that form the cytoskeletons of eukaryotic cilia and flagella are doublet MTs composed of A- and B-tubules. It is known that dynein-2 and kinesin-2, responsible for the transportation in cilia and flagella, walk on A-tubules and B-tubules, respectively. However, it is unknown how dynein-2 and kinesin-2 select A-tubules and B-tubules, respectively, while both A- and B-tubules are composed of the same alpha- and beta-tubulin dimer. Recent studies indicate that tubulin post-translational modifications (PTMs) are mostly enriched in the B- tubules. We hypothesized that the MT selection is based on the PTMs. In this study, we performed a molecular dynamics (MD) simulation to reveal how the movement of dynein-2 changes depending on the PTMs. For the effective sampling trajectories, we use a coarse-grained model for MD simulations. In the end, we found poly-glutamylation, one of the PTMs, can inhibit dynein-2 walking on MTs. Interestingly, the key residues of dynein-2 which have contact with poly-glutamylation are well reserved in many species’ dynein-2.

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