CRISPR/Cas9 technology targeting the ZnF7 domain generated two cysteine to alanine point mutations at residues 764 and 767: TGC to GCC (p.C764A) and TGC to GCT (p.C767A). Two silent mutations [GCC to GCT (A758) and TAC to TAT (Y768)] were also introduced to avoid re-editing. These mutations abrogate binding ability to polyubiquitin chains. (J:282944)