UMMS Affiliation

Department of Cell and Developmental Biology



Document Type



Axoneme; Blotting, Western; Chromatography, Gel; Dyneins; Electrophoresis, Polyacrylamide Gel; Electroporation; Fluorescent Antibody Technique; Macromolecular Substances; Microscopy, Electron; Microscopy, Fluorescence; Microtubules; *Models, Biological; Protein Binding; Rosaniline Dyes; Ultracentrifugation


Outer arm dynein (OAD) in cilia and flagella is bound to the outer doublet microtubules every 24 nm. Periodic binding of OADs at specific sites is important for efficient cilia/flagella beating; however, the molecular mechanism that specifies OAD arrangement remains elusive. Studies using the green alga Chlamydomonas reinhardtii have shown that the OAD-docking complex (ODA-DC), a heterotrimeric complex present at the OAD base, functions as the OAD docking site on the doublet. We find that the ODA-DC has an ellipsoidal shape approximately 24 nm in length. In mutant axonemes that lack OAD but retain the ODA-DC, ODA-DC molecules are aligned in an end-to-end manner along the outer doublets. When flagella of a mutant lacking ODA-DCs are supplied with ODA-DCs upon gamete fusion, ODA-DC molecules first bind to the mutant axonemes in the proximal region, and the occupied region gradually extends toward the tip, followed by binding of OADs. This and other results indicate that a cooperative association of the ODA-DC underlies its function as the OAD-docking site and is the determinant of the 24-nm periodicity.

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Citation: Proc Natl Acad Sci U S A. 2014 Jul 1;111(26):9461-6. doi: 10.1073/pnas.1403101111. Epub 2014 Jun 16. Link to article on publisher's site


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Related Resources

Link to Article in PubMed

Journal Title

Proceedings of the National Academy of Sciences of the United States of America



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