Comparative Super-Resolution Mapping of Basal Feet Reveals a Modular but Distinct Architecture in Primary and Motile Cilia

• Published in: Developmental cell 2020-10, Vol.55 (2), p.209-223.e7
• Main Authors: Nguyen, Quynh P.H., Liu, Zhen, Albulescu, Alexandra, Ouyang, Hong, Zlock, Lorna, Coyaud, Etienne, Laurent, Estelle, Finkbeiner, Walter, Moraes, Theo J., Raught, Brian, Mennella, Vito
• Format: Article
• Language: English
• Subjects: airway; Animals; appendages; basal bodies; Basal Bodies - metabolism; basal foot; Centrioles - metabolism; centrosome; cilia; Cilia - metabolism; Ciliary Motility Disorders - metabolism; electron microscopy; Humans; Life Sciences; Microscopy, Electron - methods; Microtubules - metabolism; primary ciliary dyskinesia; Proteins - metabolism; quantitative imaging; super-resolution imaging
• ISSN: 1534-5807; 1878-1551
• DOI: 10.1016/j.devcel.2020.09.015

In situ molecular architecture analysis of organelles and protein assemblies is essential to understanding the role of individual components and their cellular function, and to engineering new molecular functionalities. Through a super-resolution-driven approach, here we characterize the organization of the ciliary basal foot, an appendage of basal bodies whose main role is to provide a point of anchoring to the microtubule cytoskeleton. Quantitative image analysis shows that the basal foot is organized into three main regions linked by elongated coiled-coil proteins, revealing a conserved modular architecture in primary and motile cilia, but showing distinct features reflecting its specialized functions. Using domain-specific BioID proximity labeling and super-resolution imaging, we identify CEP112 as a basal foot protein and other candidate components of this assembly, aiding future investigations on the role of basal foot across different cilia systems. [Display omitted] •Basal foot proteins are organized into three main spatially distinct regions•The scaffolding and microtubule-anchoring regions are connected by NIN and CNTRL•NIN has a looping distribution and contributes to CNTRL primary cilia localization•BioID and super-resolution imaging identifies CEP112 as a basal foot protein Nguyen et al. show via quantitative super-resolution mapping that basal foot has a conserved yet distinct modular architecture in primary and motile cilia, reflecting its specialized function in different cilia systems. This architecture consists of three spatially separated modules that are connected by elongated coiled-coil proteins.