Primary ciliogenesis requires the distal appendage component Cep123

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Primary cilia are crucial cellular organelles involved in various signaling pathways.
• Formation of primary cilia requires precise coordination of mother centriole capping and basal body anchoring via distal appendages.

Purpose of the Study:

• To investigate the role of the distal appendage protein Cep123 in primary cilia formation.
• To determine the stage of ciliogenesis where Cep123 functions and its interacting partners.

Main Methods:

• Analysis of primary cilia formation in the absence of Cep123.
• Investigation of Cep123 interactions with known centriolar satellite proteins.
• Mapping of protein interaction domains within Cep123.

Main Results:

• Cep123 is required for the assembly, but not the maintenance, of primary cilia.
• Loss of Cep123 leads to a failure in ciliary vesicle formation, indicating a role in early ciliogenesis.
• Cep123 interacts with PCM-1, Cep290, and OFD1, mediated by its C-terminal domain.

Conclusions:

• Cep123 is a novel and essential component of the primary ciliogenesis pathway.
• The findings expand the understanding of distal appendage function in initiating primary cilia assembly.
• Cep123's interactions highlight its role in coordinating early steps of ciliogenesis.