Figure 8.

Apolipoprotein (APO) L1 is critical for the functionality of APOL1-miR193a axis. A: To evaluate the effect of APOL1 silencing on parietal epithelial cell (PEC) markers, PECs (undifferentiated) were transfected with scrambled (SCR) or APOL1 siRNAs. Protein blots control cells and transfected cells were probed for PAX2, claudin 1, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Gels from three different lysate preparations are displayed. B: Cumulative densitometric data from the above-mentioned lysates are shown in a bar diagram. APOL1 silencing in PECs with undetectable APOL1 protein enhances the expression of PEC markers. C: To assess whether APOL1 is critical for the expression of PEC transition markers, PECs were transfected with SCR or APOL1 siRNA. Control (C) and transfected cells were incubated in media that contained vehicle, vitamin D receptor (VDR) agonist (100 nmol/L), interferon (IFN)-γ (10 ng/mL), or miR193a inhibitor (miR, 50 nmol/L) for 48 hours. In parallel sets of experiments, C and transfected cells were transduced with HIV (NL4-3; 10³ green fluorescent protein–expressing units/mL). Protein blots were probed for APOL1 and reprobed for Wilms' tumor 1 (WT1) and GAPDH. Representative protein gel blots are displayed. D: Cumulative densitometric data of protein blots from C are shown in bar graphs. E: Protein gel blots from the cellular lysates used in 8C were probed for α-actinin, podocalyxin (PDX), and GAPDH. Representative blots are displayed. F: Cumulative densitometric data of protein blots from E are shown in a bar diagram. n = 4. ^∗P < 0.05, ^∗∗P < 0.01 versus respective control and SCR (B); ^†P < 0.05, ^††P < 0.01 versus respective C and VDR agonist + siAPOL1; ^‡P < 0.05 versus respective C and IFN-Y + siAPOL1; ^§P < 0.05 versus respective C and HIV and siAPOL1; ^§§P < 0.01 versus respective C and HIV + siAPOL1; ^¶P < 0.05 versus respective C and miR193a inh + siAPOL1 (D and F); ^‖P < 0.05 versus respective C (F). VDA, VDR agonist.