CYCS and Parkinson disease: Additionally, the KEGG pathway enrichment analysis revealed terms such as Parkinson’s disease (mmu05012), Huntington disease (mmu05016) and Alzheimer’s disease (mmu05010), which contain many genes encoding mitochondrial proteins (e.g. cytochrome oxidase 7a1/Cox7a1, ATP-synthase subunit 5h/Atp5h and cytochrome c/Cycs) to be downregulated in NiPKOs (Fig 5B and 5C, S4 Table).