The function of ENSG00000156222 (SLC28A1, solute carrier family 28 member 1) is as follows. Sodium and pyrimidine nucleoside symporter of the plasma membrane that imports uridine, thymidine and cytidine into cells by coupling their transport to the transmembrane sodium electrochemical gradient. Also transports adenosine, an atypical substrate transported with high apparent affinity, but low maximum velocity. Therefore, exhibits the transport characteristics of the nucleoside transport system cit or N2 subtype (N2/cit) (PubMed:10455109, PubMed:14701834, PubMed:15194733, PubMed:21795683, PubMed:21998139, PubMed:30658162, PubMed:32126230, PubMed:9124315). Involved in renal nucleoside (re)absorption (PubMed:30658162). {ECO:0000269|PubMed:10455109, ECO:0000269|PubMed:14701834, ECO:0000269|PubMed:15194733, ECO:0000269|PubMed:21795683, ECO:0000269|PubMed:21998139, ECO:0000269|PubMed:30658162, ECO:0000269|PubMed:32126230, ECO:0000269|PubMed:9124315}.