Receptor for the neuroprotective and glioprotective factor prosaposin. Ligand binding induces endocytosis, followed by an ERK phosphorylation cascade (By similarity). Forms a complex with PRKN, STUB1 and HSP70. The amount of STUB1 in the complex increases during ER stress. STUB1 promotes the dissociation of HSP70 from PRKN, thus facilitating PRKN-mediated GPR37 ubiquitination. Interacts with PACRG (By similarity). Ubiquitinated by PRKN in the presence of ubiquitin-conjugating enzymes in the endoplasmic reticulum. Belongs to the G-protein coupled receptor 1 family.