1u2z
From Proteopedia
Crystal structure of histone K79 methyltransferase Dot1p from yeast
Overview
Methylation of Lys79 on histone H3 by Dot1p is important for gene silencing. The elongated structure of the conserved core of yeast Dot1p contains an N-terminal helical domain and a seven-stranded catalytic domain that harbors the binding site for the methyl-donor and an active site pocket sided with conserved hydrophobic residues. The S-adenosyl-L-homocysteine exhibits an extended conformation distinct from the folded conformation observed in structures of SET domain histone lysine methyltransferases. A catalytic asparagine (Asn479), located at the bottom of the active site pocket, suggests a mechanism similar to that employed for amino methylation in DNA and protein glutamine methylation. The acidic, concave cleft between the two domains contains two basic residue binding pockets that could accommodate the outwardly protruding basic side chains around Lys79 of histone H3 on the disk-like nucleosome surface. Biochemical studies suggest that recombinant Dot1 proteins are active on recombinant nucleosomes, free of any modifications.
About this Structure
1U2Z is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Structure of the conserved core of the yeast Dot1p, a nucleosomal histone H3 lysine 79 methyltransferase., Sawada K, Yang Z, Horton JR, Collins RE, Zhang X, Cheng X, J Biol Chem. 2004 Oct 8;279(41):43296-306. Epub 2004 Jul 29. PMID:15292170 Page seeded by OCA on Sat May 3 10:41:35 2008
