The ATRX-ADD domain binds to H3 tail peptides and reads the combined methylation state of K4 and K9.

Abstract

Mutations in the ATRX protein are associated with the alpha-thalassemia and mental retardation X-linked syndrome (ATR-X). Almost half of the disease-causing mutations occur in its ATRX-Dnmt3-Dnmt3L (ADD) domain. By employing peptide arrays, chromatin pull-down and peptide binding assays, we show specific binding of the ADD domain to H3 histone tail peptides containing H3K9me3. Peptide binding was disrupted by the presence of the H3K4me3 and H3K4me2 modification marks indicating that the ATRX-ADD domain has a combined readout of these two important marks (absence of H3K4me2 and H3K4me3 and presence of H3K9me3). Disease-causing mutations reduced ATRX-ADD binding to H3 tail peptides. ATRX variants, which fail in the H3K9me3 interaction, show a loss of heterochromatic localization in cells, which indicates the chromatin targeting function of the ADD domain of ATRX. Disruption of H3K9me3 binding may be a general pathogenicity pathway of ATRX mutations in the ADD domain which may explain the clustering of disease mutations in this part of the ATRX protein.

• Authors: Arunkumar Dhayalan, Raluca Tamas, Ina Bock, Anna Tattermusch, Emilia Dimitrova, Srikanth Kudithipudi, Sergey Ragozin, Albert Jeltsch
• Journal: Human molecular genetics (Hum Mol Genet) Vol. 20 Issue 11 Pg. 2195-203 (Jun 01 2011) ISSN: 1460-2083 [Electronic] England
• PMID: 21421568 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Chromatin
• Histones
• Nuclear Proteins
• Peptides
• DNA Helicases
• ATRX protein, human
• Atrx protein, mouse
• X-linked Nuclear Protein
• Lysine

Topics

• 3T3 Cells
• Amino Acid Sequence
• Animals
• Chromatin (metabolism)
• Cloning, Molecular
• DNA Helicases (genetics, metabolism)
• Gene Expression
• HEK293 Cells
• Histones (metabolism)
• Humans
• Lysine (genetics, metabolism)
• Mental Retardation, X-Linked (genetics, pathology)
• Methylation
• Mice
• Molecular Sequence Data
• Mutagenesis, Site-Directed
• Mutation
• Nuclear Proteins (genetics, metabolism)
• Peptides (metabolism)
• Protein Binding
• Protein Interaction Domains and Motifs
• Protein Structure, Quaternary
• X-linked Nuclear Protein
• alpha-Thalassemia (genetics, pathology)