Investigation of Endoplasmic Reticulum Stress in P3H2-Knockout Immortalized Human Podocyte Cell Line

Prolyl 3-hydroxylase 2 (P3H2) is an enzyme that catalyzes the post-translational modification of collagen IV, a key structural component of the glomerular basement membrane (GBM) in podocytes. While P3H2 loss has been linked to kidney diseases characterized by basement membrane defects, its cellular effects remain unclear. This study aimed to evaluate whether P3H2 deficiency induces endoplasmic reticulum (ER) stress in an immortalized human podocyte cell line. Previously generated P3H2-Knockout (KO) podocytes were used and compared to wild-type (WT) controls. ER stress was assessed by measuring mRNA and protein levels of ER stress markers via quantitative PCR (qPCR) and Western blot. Immunofluorescence staining was performed to examine collagen IV localization. Results showed no significant differences in ER stress marker expression at the RNA and protein levels between WT and KO cells. Collagen IV localization was similarly observed in the plasma membrane and cytoplasm of both groups. These findings indicate that P3H2 loss does not induce ER stress in podocytes under basal conditions; however, further investigation is required to better understand the impact of P3H2 deficiency on podocyte function.