Suppression of ORP150 expression abolishes the effects of AMPK on ER stress and apoptosis. A, HepG2 cells were transfected with ORP150-specific or scrambled siRNA (100 nm) for 48 h. Proteins were extracted and immunoblotted for ORP150 and β-actin. B–F, forty-eight hours after the siRNA transfection, HepG2 cells were treated with palmitic acid (PA) alone or in the presence of AICAR (1 mm) for 24 h. ER stress markers (B), Ddit3 (C), and sXbp1 mRNA levels (D), TUNEL staining (E), and caspase-3 activity (F). *, p < 0.05.