The team of Laurent KODJABACHIAN (Biology of Ciliated Epithelia, IBDM) and Pascal BARBRY (IPMC, Sophia-Antipolis) report in NATURE COMMUNICATIONS about new components of the DEUTEROSOME, an enigmatic organelle that supports massive centriole synthesis in multiciliated cells (MCCs). MCCs harbor dozens to hundreds of motile cilia, which emerge from centrioles docked at the apical surface to generate hydrodynamic forces important for animal physiology across evolution. In humans, MCCs support mucociliary clearance of airways, circulation of cerebrospinal fluid in the nervous system and transportation of gametes in genital tracts. Looking for unknown deuterosome components, the authors used single-cell RNA sequencing to characterize the transcriptome of MCCs at the stage of centriole synthesis. They further analyzed the function of CDC20B (a relative of the cell cycle regulator CDC20), that had never been studied before. Using Xenopus and mouse, they collected evidence that CDC20B associates to deuterosomes to help the release of newly synthesized centrioles. This work reveals that centriole synthesis in vertebrate MCCs involve adaptation between ancestral components of the centriole duplication machinery, and newly evolved cell-cycle related molecules, such as CDC20B.

Fig Revinski et al IBDM website

A. Confocal picture of ciliated Xenopus embryonic epidermis. Cilia are stained in green and cell junctions in white. B. Confocal picture of postnatal mouse ependymal ciliated epithelium. Cilia are stained in green and cell junctions in red. C. STED super-resolution imaging in mouse reveals the architecture of peri-deuterosomal material (PCNT in magenta, g-Tub in blue). D. Model highlighting the analogy between centriole disengagement at mitosis and centriole release from deuterosomes in MCCs. The latter involves CDC20B a protein that emerged during evolution of vertebrate MCCs.

 

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