Cytosolic peptide: N -glycanase (NGLY1) is a widely conserved enzyme involved in de- N -glycosylation of N -glycosylated proteins. Mutations in the human NGLY1 gene cause global developmental delay and multisystemic symptoms, but the molecular mechanism underlying pathogenesis remains poorly understood. FBXO6/FBS2, a subunit of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex ....