Enables small molecule binding activity. Involved in several processes, including detection of stimulus involved in sensory perception of pain; endothelium development; and nervous system development. Located in endosome; nucleus; and plasma membrane. Used to study pulmonary hypertension and temporal lobe epilepsy. Human ortholog(s) of this gene implicated in WHIM syndrome; hematologic cancer (multiple); leukopenia; osteoporosis; and pancreatic adenocarcinoma. Orthologous to human CXCR4 (C-X-C motif chemokine receptor 4). [provided by Alliance of Genome Resources, Apr 2022]