The function of SLC4A4 (solute carrier family 4 member 4, ENSG00000080493) is as follows. Electrogenic sodium/bicarbonate cotransporter with a Na(+):HCO3(-) stoichiometry varying from 1:2 to 1:3. May regulate bicarbonate influx/efflux at the basolateral membrane of cells and regulate intracellular pH. {ECO:0000269|PubMed:10069984, ECO:0000269|PubMed:11744745, ECO:0000269|PubMed:12411514, ECO:0000269|PubMed:12730338, ECO:0000269|PubMed:12907161, ECO:0000269|PubMed:14567693, ECO:0000269|PubMed:15218065, ECO:0000269|PubMed:15713912, ECO:0000269|PubMed:15817634, ECO:0000269|PubMed:15930088, ECO:0000269|PubMed:16636648, ECO:0000269|PubMed:16769890, ECO:0000269|PubMed:17661077, ECO:0000269|PubMed:23324180, ECO:0000269|PubMed:23636456, ECO:0000269|PubMed:29500354, ECO:0000269|PubMed:9235899, ECO:0000269|PubMed:9651366}.