Characterizing the Roles of C1orf198 in Centriole and Primary Cilium Formation and Function

Centrioles are microtubule-based structures of the cell that are important in forming the centrosomes and primary cilium, which play a critical role in cell division, signaling, and development. Through a large-scale proteomics study of centriolar proteins, we found that an uncharacterized protein, Chromosome 1 Open Reading Frame 198 (C1ORF198), is a candidate interactor of known centriolar and ciliary proteins. Our findings indicate that C1ORF198 localizes to the centriole throughout the cell cycle, primarily during interphase, and at the base of the primary cilium. Depletion or knockout of C1ORF198 resulted in an amplification of the centriole number, thus, suggesting that it regulates the fidelity of centriole duplication through an unknown mechanism. Moreover, C1ORF198 is overexpressed in certain cancer lines, and may play a role in primary cilium formation. Using a combination of functional, localization, and proteomic assays, we seek to delineate C1ORF198 function in human cells.