6L4P

Crystal structure of the complex between the axonemal outer-arm dynein light chain-1 and microtubule binding domain of gamma heavy chain

Summary for 6L4P

• Entry DOI: 10.2210/pdb6l4p/pdb
• Descriptor: Dynein light chain 1, axonemal, Flagellar outer dynein arm heavy chain gamma, PHOSPHATE ION, ... (6 entities in total)
• Functional Keywords: motor protein, complex, contractile protein-motor protein complex, contractile protein/motor protein
• Biological source: Chlamydomonas reinhardtii; More
• Total number of polymer chains: 2
• Total formula weight: 38712.36

Authors

Toda, A.,Nishikawa, Y.,Tanaka, H.,Yagi, T.,Kurisu, G. (deposition date: 2019-10-19, release date: 2020-02-19, Last modification date: 2023-11-22)

Primary citation

Toda, A.,Nishikawa, Y.,Tanaka, H.,Yagi, T.,Kurisu, G.
The complex of outer-arm dynein light chain-1 and the microtubule-binding domain of the gamma heavy chain shows how axonemal dynein tunes ciliary beating.
J.Biol.Chem., 295:3982-3989, 2020

PubMed Abstract: Axonemal dynein is a microtubule-based molecular motor that drives ciliary/flagellar beating in eukaryotes. In axonemal dynein, the outer-arm dynein (OAD) complex, which comprises three heavy chains (α, β, and γ), produces the main driving force for ciliary/flagellar motility. It has recently been shown that axonemal dynein light chain-1 (LC1) binds to the microtubule-binding domain (MTBD) of OADγ, leading to a decrease in its microtubule-binding affinity. However, it remains unclear how LC1 interacts with the MTBD and controls the microtubule-binding affinity of OADγ. Here, we have used X-ray crystallography and pulldown assays to examine the interaction between LC1 and the MTBD, identifying two important sites of interaction in the MTBD. Solving the LC1-MTBD complex from at 1.7 Å resolution, we observed that one site is located in the H5 helix and that the other is located in the flap region that is unique to some axonemal dynein MTBDs. Mutational analysis of key residues in these sites indicated that the H5 helix is the main LC1-binding site. We modeled the ternary structure of the LC1-MTBD complex bound to microtubules based on the known dynein-microtubule complex. This enabled us to propose a structural basis for both formations of the ternary LC1-MTBD-microtubule complex and LC1-mediated tuning of MTBD binding to the microtubule, suggesting a molecular model for how axonemal dynein senses the curvature of the axoneme and tunes ciliary/flagellar beating.

PubMed: 32014992
DOI: 10.1074/jbc.RA119.011541

Experimental method

X-RAY DIFFRACTION (1.703 Å)