Crystal structure of the stalk region of axonemal inner-arm dynein-d reveals unique features in the coiled-coil and microtubule-binding domain.
Ko, S., Toda, A., Tanaka, H., Yu, J., Kurisu, G.(2023) FEBS Lett 597: 2149-2160
- PubMed: 37400274 
- DOI: https://doi.org/10.1002/1873-3468.14690
- Primary Citation of Related Structures:  
8I3J - PubMed Abstract: 
Axonemal dynein is an ATP-dependent microtubular motor protein responsible for cilia and flagella beating, and its dysfunction can cause diseases such as primary ciliary dyskinesia and sperm dysmotility. Despite its biological importance, structure-based mechanisms underlying axonemal dynein motors remain unclear. Here, we determined the X-ray crystal structure of the human inner-arm dynein-d (DNAH1) stalk region, which contains a long antiparallel coiled-coil and a microtubule-binding domain (MTBD), at 2.7 Å resolution. Notably, differences in the relative orientation of the coiled-coil and MTBD in comparison with other dyneins, as well as the diverse orientations of the MTBD flap region among various isoforms, lead us to propose a 'spike shoe model' with an altered stepping angle for the interaction between IAD-d and microtubules. Based on these findings, we discuss isoform-specific functions of the axonemal dynein stalk MTBDs.
Organizational Affiliation: 
Protein Crystallography Laboratory, Institute for Protein Research, Osaka University, Suita, Japan.