OPTN and Alzheimer disease: A decreased expression of the proteins that play integral roles in autophagy and mitophagy machinery has been observed in fibroblasts from AD brains, such as ULK1, AMBRA1, BNIP3, NIX/BNIP3L, FUNDC1, VDAC1, VCP/P97, OPTN, ATG5, ATG12, and Beclin-1 [141].