Abstract: Craniofacial differences are among the most common congenital disorders in humans. There are many regulatory factors at play during development of the head and face, with much left to understand. The dysfunction of the ciliogenesis and planar polarity effectors (CPLANE) are a known cause of human Orofaciodigital Disorders (OFD). The Rsg1 subunit of CPLANE is essential for ciliary function, but it remains among the least-studied components, and its mechanisms of action remain largely unexplored. Importantly, my preliminary data suggest that Rsg1 interacts with Fam92, Chibby, and Dzip1, proteins required for basal body docking and transition zone assembly. In this proposed research, the craniofacial developmental differences after disruption of Rsg1 and Fam92 will be explored in a model animal, with a specific focus on neural crest development. In vivo live imaging of ciliated cells will be studied to determine the cellular function of these proteins. Lastly, the biochemical function of the Fam92 BAR domains and disordered regions for membrane morphology will be explored in in vitro systems. Thus, the whole embryo, cellular, and biochemical functions of ciliary proteins Rsg1 and the Fam92- Chibby-Dzip1 module will be elucidated by the proposed work, which in turn will advance our understanding of congenital craniofacial disorders.