Histone-lysine N-methyltransferase, H3 lysine-9 specific (EC 2.1.1.355) (EC 2.1.1.366) (EC 2.1.1.367) (Cryptic loci regulator 4) (Histone H3-K9 methyltransferase) (H3-K9-HMTase) (HKMT) (Lysine N-methyltransferase 1) (Protein lysine methyltransferase clr4) (PKMT)