Myristoylated Neuronal Calcium Sensor-1 captures the ciliary vesicle at distal appendages
Abstract
The primary cilium is a microtubule-based organelle that cycles through assembly and disassembly. In many cell types, formation of the cilium is initiated by recruitment of ciliary vesicles to the distal appendage of the mother centriole. However, the distal appendage mechanism that directly captures ciliary vesicles is yet to be identified. In an accompanying paper, we show that the distal appendage protein, CEP89, is important for the ciliary vesicle recruitment, but not for other steps of cilium formation (Tomoharu Kanie, Love, Fisher, Gustavsson, & Jackson, 2023). The lack of a membrane binding motif in CEP89 suggests that it may indirectly recruit ciliary vesicles via another binding partner. Here, we identify Neuronal Calcium Sensor-1 (NCS1) as a stoichiometric interactor of CEP89. NCS1 localizes to the position between CEP89 and a ciliary vesicle marker, RAB34, at the distal appendage. This localization was completely abolished in CEP89 knockouts, suggesting that CEP89 recruits NCS1 to the distal appendage. Similarly to CEP89 knockouts, ciliary vesicle recruitment as well as subsequent cilium formation was perturbed in NCS1 knockout cells. The ability of NCS1 to recruit the ciliary vesicle is dependent on its myristoylation motif and NCS1 knockout cells expressing a myristoylation defective mutant failed to rescue the vesicle recruitment defect despite localizing properly to the centriole. In sum, our analysis reveals the first known mechanism for how the distal appendage recruits the ciliary vesicles.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for corresponding figures.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (P20GM103447)
- Tomoharu Kanie
National Institute of General Medical Sciences (1R35GM151013)
- Tomoharu Kanie
National Institute of General Medical Sciences (R01GM114276)
- Peter K Jackson
National Institute of General Medical Sciences (R01GM121565)
- Peter K Jackson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All mice were maintained under specific pathogen-free conditions at the Stanford animal care facility. All experiments were approved by Administrative Panel on Laboratory Animal Care at Stanford University (Institutional Animal Care and Use Committee protocol number: 28556) and were performed in strict accordance with their guidelines.
Copyright
© 2025, Kanie et al.
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