Figure 6.

APOL3 Exhibits K⁺ Channel Activity Influencing Intracellular Ca²⁺ Levels

(A) APOL3 channel activity in planar soy lipid membranes (n = 5).

(B) Model of APOL-mediated ion currents in the podocyte ER and Golgi membranes.

(C) Effects of APOL1 or APOL1Δ on APOL3 channel activity. APOL3, APOL1, and NCS-1 were added at 56, 59, and 109 pmol/mL (n values indicated in the table).

(D) Quantification of the peak of cytosolic Ca²⁺ increases in response to different ATP concentrations (n = 5). The values were normalized to the signal obtained using 100 μM ATP.

(E) Intracellular Ca²⁺ store contents. In the top panels, each curve is representative of one single experiment (calculated from three technical replicates). In the lower panels, data were quantified by calculating the area under the curve (AUC) normalized versus the WT cell line (black line). In the dot plots, each cell line is represented with a different color and each independent experiment is represented with a different symbol (left panel, n = 9; center and right panels, n = 7). Data belonging to the same experiment (e.g., 96-well plate) are indicated with the same symbol.