In this study, we investigated the involvement of the ubiquitin-proteasome system (UPS) and the autophagy-lysosome pathway, two major intracellular protein quality control systems, in the regulation of wild-type (WT) OPTN, ALS-linked mutant E478G OPTN and POAG-linked mutant E50K OPTN.
Analysis of cell transfection showed that the nonsense and missense mutations of OPTN abolished the inhibition of activation of nuclear factor kappa B (NF-kappaB), and the E478G mutation revealed a cytoplasmic distribution different from that of the wild type or a POAG mutation.