DISC1 represents a key molecular hub underpinning a number of fundamental cellular functions and although peptides do not readily pass the blood-brain barrier, our cell-permeable peptides provide powerful tools to further elucidate the DISC1 biology underpinning neurodevelopment and psychosis and may open new routes to provide substrate-specific FBXW7 inhibitors for therapeutic use. Here, DISC1 is linked to psychotic disorder.