||Mediates both influx and efflux of nucleosides across the membrane (equilibrative transporter). Mediates transport of adenine, adenosine and uridine, as well as several nucleoside analog drugs, such as anticancer and antiviral agents, including cladribine, cordycepin, tubercidin and AZT. Does not transport hypoxanthine.
||Widely expressed in both adult and fetal tissues. Highest levels in placenta, uterus, ovary, spleen, lymph node and bone marrow. Lowest levels in brain and heart.
|Involvement in Disease:
||Histiocytosis-lymphadenopathy plus syndrome: A syndrome characterized by the combination of features from 2 or more of four histiocytic disorders, originally thought to be distinct: Faisalabad histiocytosis (FHC), sinus histiocytosis with massive lymphadenopathy (SHML), H syndrome, and pigmented hypertrichosis with insulin-dependent diabetes mellitus syndrome (PHID). FHC features include joint deformities, sensorineural hearing loss, and subsequent development of generalized lymphadenopathy and swellings in the eyelids that contain histiocytes. SHML causes lymph node enlargement in children frequently accompanied by fever, leukocytosis, elevated erythrocyte sedimentation rate, and polyclonal hypergammaglobulinemia. H syndrome is characterized by cutaneous hyperpigmentation and hypertrichosis, hepatosplenomegaly, heart anomalies, and hypogonadism; hearing loss is found in about half of patients. PHID is characterized by predominantly antibody-negative insulin-dependent diabetes mellitus associated with pigmented hypertrichosis and variable occurrence of other features of H syndrome.
||Belongs to the SLC29A/ENT transporter (TC 2.A.57) family.
||Membrane. Late endosome membrane. Lysosome membrane.
Observed in a punctate intracellular pattern showing partial colocalization with late endosomes/lysosomes. Not detected at the cell surface.