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bioRxiv · 10.1101/2024.10.04.616628

The A-C Linker controls centriole cohesion and duplication

Bournonville, L.·Laporte, M. H.·Borgers, S.·Guichard, P.·Hamel, V.
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Abstract

Centrioles are evolutionarily conserved barrel-shaped organelles playing crucial roles in cell division and ciliogenesis. These functions are underpinned by specific structural sub-elements whose functions have been under investigation since many years. The A- C linker structure, connecting adjacent microtubule triplets in the proximal region, has remained unexplored due to its unknown composition. Here, using ultrastructure expansion microscopy, we characterized two recently identified A-C linker proteins, CCDC77 and WDR67, along with a newly discovered protein, MIIP. Our findings reveal that these proteins localize between microtubule triplets at the A-C linker, forming a complex. Depletion of A-C linker components disrupt microtubule triplet cohesion, leading to breakage at the proximal end. Co-removal of the A-C linker and the inner scaffold demonstrates their joint role in maintaining centriole architecture. Moreover, we uncover an unexpected function of the A-C linker in centriole duplication through torus regulation, underscoring the interplay between these protein modules.

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Bournonville, L., Laporte, M. H., Borgers, S., Guichard, P., Hamel, V.. 2024-10-04. The A-C Linker controls centriole cohesion and duplication. https://doi.org/10.1101/2024.10.04.616628

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