This entry represents SYS1 homologues (hSYS1). hSYS1 is a multi-pass membrane protein found in the Golgi apparatus membrane. hSYS1 appears to be involved in protein trafficking and may serve as a receptor for ARFRP1 (Arf-related protein 1), the human homologues of Arl3p []. Arf family members are GTPases that are crucial for the organisation of membrane traffic. They act by recruiting coat proteins to form transport vesicles, and motor proteins to move both transport carriers and organelles []. Arfs can also carry lipid modifications that are involved in membrane recruitment. The function of hSYS1 is unknown, but it controls the location of ARFRP1, apparently by forming a complex with the protein, and could therefore function in the Arl3p/Arl1p pathway.
