SET domain (including pre-SET and post-SET domains) found in SET domain and mariner transposase fusion protein (SETMAR) and similar proteins
SETMAR (also termed metnase) is a DNA-binding protein that is indirectly recruited to sites of DNA damage through protein-protein interactions. It has a sequence-specific DNA-binding activity recognizing the 19-mer core of the 5'-terminal inverted repeats (TIRs) of the Hsmar1 element and displays a DNA nicking and end joining activity. SETMAR also acts as a histone-lysine N-methyltransferase that methylates 'Lys-4' and 'Lys-36' of histone H3. It specifically mediates dimethylation of H3 'Lys-36' at sites of DNA double-strand break and may recruit proteins required for efficient DSB repair through non-homologous end-joining.