(A) Sequence alignment of human PRMT active sites showing site of N265Y mutation generated using ClustalW and Box Shade. The site targeted for mutagenesis is highlighted in yellow. Sites that show >50% consensus are shaded (black for identical residues and grey for similar residues). Colour coding matches the structures shown in (B). (B) Superposition of PRMT1 (1OR8, hot pink [50]), PRMT2 (5JMQ, yellow), PRMT3 (1F3L, green [51]) and PRMT8 (5DST, blue [52]) with CARM1 (WT) (bound to 9, light grey, all monomers in the asymmetric unit shown) and CARM1-N265Y (bound to 10, teal), which all have a tyrosine or phenylalanine adjacent to the active site glutamate.