Intraflagellar transport of tubulin maintains steady-state axoneme integrity in C. elegans cilia

Loseva, E.; Mitra, A.; Groskamp, D.; Peterman, E. J. G.

doi:10.64898/2026.04.14.718528

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bioRxiv · 10.64898/2026.04.14.718528

Intraflagellar transport of tubulin maintains steady-state axoneme integrity in C. elegans cilia

Loseva, E.·Mitra, A.·Groskamp, D.·Peterman, E. J. G.

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Abstract

The integrity of the axoneme - the microtubule (MT)-based core of the cilium - and intraflagellar transport (IFT) are interdependent. The mechanisms determining axoneme structure and dynamics have remained largely unknown, especially in primary cilia with a more variable architecture and longer MT singlet parts. Using fluorescence imaging in the phasmid neurons of C. elegans, we here demonstrate that {beta}-tubulin isotype TBB-4 diffuses through the dendrite and employs a combination of anterograde IFT and diffusion to reach the sites of incorporation in the steady-state axoneme. Disrupting tubulins ability to bind to the IFT significantly reduces its share in the axoneme. We suggest that, in phasmid cilia, a constant supply of tubulin by IFT is required for steady-state length maintenance, in order to elevate soluble tubulin concentration near the axonemal tips and to promote MT stability.

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Loseva, E., Mitra, A., Groskamp, D., Peterman, E. J. G.. 2026-04-15. Intraflagellar transport of tubulin maintains steady-state axoneme integrity in C. elegans cilia. https://doi.org/10.64898/2026.04.14.718528

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