Ras-related protein Rab-8A is a protein that in humans is encoded by the RAB8A gene. It is mapped to 19p13.12. The protein encoded by this gene is a member of the RAS superfamily which are small GTP/GDP-binding proteins with an average size of 200aa. The RAS-related proteins of the RAB/YPT family may play a role in the transport of proteins from the endoplasmic reticulum to the Golgi and the plasma membrane. RAB8A regulates cilia assembly by targeting and promoting fusion of vesicles near the ciliary membrane. This gene requires CEP290 for centrosome localization and that CEP290 regulates entry of RAB8A into the cilium during assembly of this organelle. RAB8A has been shown to interact with Optineurin and MAP4K2.