Patent ID: 8221993

Claim:
A method of measuring methyl transferase activity of a polypeptide, said method comprising the steps of: a. contacting a polypeptide selected from the group consisting of: i. a polypeptide comprising the amino acid sequence of SEQ ID NO: 51 (ZNFN3A1); and ii. a polypeptide that comprises the amino acid sequence having at least about 95% identity to SEQ ID NO: 51 in which both of NHSCDPN (SEQ ID NO:52) and GEELTICY (SEQ ID NO:53) are conserved, wherein the polypeptide has a methyltransferase activity for histone H3; with a substrate to be methylated and a cofactor under conditions capable of methylation of the substrate; b. detecting the methylation level of the substrate; and c. measuring the methyl transferase activity by correlating the methylation level of step (b) with the methyl transferase activity.