Then, we assessed mitochondrial function by measuring the generation of reactive oxygen species (ROS) in mitochondria using MitoSOX, the mitochondrial membrane potential (Δψm) using tetramethylrhodamine methyl ester (TMRM), and the O2 consumption rate, in our NSC34 cells subjected to ER stress with or without GRP78 overexpression. Here, HSPA5 is linked to Endoplasmic Reticulum Stress.