Fig. 3.

The mechanism causing the increase in sodium transport in RPTCs carrying the SLC4A5 rs10177833 is shown on the same model depicted in Fig. 1. These RPTCs have an increase in HNF4A binding to the SLC4A5 gene resulting in an increase in NBCe2 mRNA, as well as an increase in NBCe2 protein and activity under high salt conditions. The resulting increase in intracellular sodium and bicarbonate is associated with an increase in PAT1 activity and slight reduction in NBCe1 activity