The indicated regions of the DUF1669 domains of the FAM83 proteins are aligned using the Clustal Omega and BoxShade server. Identical residues conserved in more than 50% of the sequences are boxed in black and similar residues are boxed in grey. The conserved Asp (D) and Phe (F) residues, which abolish CK1 interaction when individually mutated to Ala (A), are indicated. Interestingly, the same Asp (D) residue is part of the HKD motif in FAM83 proteins.