Abstract
Histone modifications have important roles in transcriptional control, mitosis and heterochromatin formation. G9a and G9a-like protein (GLP) are euchromatin-associated methyltransferases that repress transcription by mono- and dimethylating histone H3 at Lys9 (H3K9). Here we demonstrate that the ankyrin repeat domains of G9a and GLP bind with strong preference to N-terminal H3 peptides containing mono- or dimethyl K9. X-ray crystallography revealed the basis for recognition of the methylated lysine by a partial hydrophobic cage with three tryptophans and one acidic residue. Substitution of key residues in the cage eliminated the H3 tail interaction. Hence, G9a and GLP contain a new type of methyllysine binding module (the ankyrin repeat domains) and are the first examples of protein (histone) methyltransferases harboring in a single polypeptide the activities that generate and read the same epigenetic mark.
Original language | English (US) |
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Pages (from-to) | 245-250 |
Number of pages | 6 |
Journal | Nature Structural and Molecular Biology |
Volume | 15 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2008 |
Externally published | Yes |
ASJC Scopus subject areas
- Structural Biology
- Molecular Biology