Acts as component of the GARP complex that is involved in retrograde transport from early and late endosomes to the trans-Golgi network (TGN). The GARP complex is required for the maintenance of the cycling of mannose 6-phosphate receptors between the TGN and endosomes, this cycling is necessary for proper lysosomal sorting of acid hydrolases such as CTSD (PubMed:15878329, PubMed:18367545). Acts as component of the EARP complex that is involved in endocytic recycling. The EARP complex associates with Rab4-positive endosomes and promotes recycling of internalized transferrin receptor (TFRC) to the plasma membrane (PubMed:25799061). Component of the Golgi-associated retrograde protein (GARP) complex, also called VFT (VPS fifty-three) complex, composed of VPS51, VPS52, VPS53 and VPS54 (PubMed:27440922, PubMed:15878329, PubMed:20685960). Component of the endosome-associated retrograde protein (EARP) complex, composed of VPS51, VPS52, VPS53 and VPS50/Syndetin (PubMed:25799061, PubMed:27440922). EIPR1 interacts with both EARP and GARP complexes and mediates the recruitment of the GARP complex to the trans-Golgi network (PubMed:27440922). Interacts with RAB6A and STX10 (PubMed:15878329, PubMed:20685960). Interacts with UHRF1BP1L (PubMed:20163565). Localizes to the trans-Golgi network as part of the GARP complex, while it localizes to recycling endosomes as part of the EARP complex (PubMed:25799061). Belongs to the VPS52 family.