Fig. 5.

S-protein induces ER stress in ARPE-19 cells. A and B Immunofluorescence staining of S-protein in S-protein-treated (B) or Flag-S overexpressed ARPE-19 cells (A) that were transfected with pDs-Red-KDEL. C Immunoblot of the expression of CHOP, BIP, Calnexin, ATF3, ATF4, ATF6, and β-actin in ARPE-19 cells treated with S-protein or treated with S-protein S-protein + NAC for 24 h. D Densitometry quantitation of those proteins in C. The data represent mean ± SD (n = 3), *p < 0.05, **p < 0.01