MUL1 and Alzheimer disease: Additionally, in iPSC-derived cortical neurons, the levels of other mitophagy-related proteins like FUNDC1, Bcl2L13, AMBRA1 (BECN1-regulated autophagy protein 1), and MUL1 (mitochondrial ubiquitin ligase activator of NFKB-1) were also shown to be decreased, further confirming the impairment of mitophagy in AD.