Q9NQR1

SETD8 also designated Pr-Set7, SET8 is a nucleosome-specific monomethylase that specifically methylates H4 at Lys 20, a mark of constitutive and facultative heterochromatin. Pr-Set7 is a single subunit enzyme and prefers nucleosomal substrates. It functions to regulate cell-cycle-dependent transcriptional silencing and mitotic regulation in metazoans. The amino acid sequence RHRKVLRDN (17-25) is required for the SET domain of Pr-Set7 to function and, thus, for multiplicity of methylation of Lys 20 of H4 to occur. The methylation mark is very stable and is maintained even in the absence of Pr-Set7.