Solution structure of the ADD domain of ATRX complexed with histone tail H3 1-15 K9me3
[ATRX_HUMAN] Defects in ATRX are the cause of alpha-thalassemia mental retardation syndrome X-linked (ATRX) [MIM:301040]. ATR-X is an X-linked disorder comprising severe psychomotor retardation, facial dysmorphism, urogenital abnormalities, and alpha-thalassemia. An essential phenotypic trait are hemoglobin H erythrocyte inclusions.          Defects in ATRX are the cause of mental retardation syndromic X-linked with hypotonic facies syndrome type 1 (MRXSHF1) [MIM:309580]; also called Carpenter-Waziri syndrome (CWS), Juberg-Marsidi syndrome (JMS), Smith-Fineman-Myers syndrome type 1 (SFM1). Clinical features include severe mental retardation, dysmorphic facies, and a highly skewed X-inactivation pattern in carrier women. Other more variable features include hypogonadism, deafness, renal anomalies, and mild skeletal defects.      Defects in ATRX are a cause of alpha-thalassemia myelodysplasia syndrome (ATMDS) [MIM:300448]. In this disorder, alpha-thalassemia occurs as an acquired abnormality in association with a multilineage myelodysplasia.
[ATRX_HUMAN] Could be a global transcriptional regulator. Modifies gene expression by affecting chromatin. May be involved in brain development and facial morphogenesis.
Publication Abstract from PubMed
Accurate read-out of chromatin modifications is essential for eukaryotic life. Mutations in the gene encoding X-linked ATRX protein cause a mental-retardation syndrome, whereas wild-type ATRX protein targets pericentric and telomeric heterochromatin for deposition of the histone variant H3.3 by means of a largely unknown mechanism. Here we show that the ADD domain of ATRX, in which most syndrome-causing mutations occur, engages the N-terminal tail of histone H3 through two rigidly oriented binding pockets, one for unmodified Lys4 and the other for di- or trimethylated Lys9. In vivo experiments show this combinatorial readout is required for ATRX localization, with recruitment enhanced by a third interaction through heterochromatin protein-1 (HP1) that also recognizes trimethylated Lys9. The cooperation of ATRX ADD domain and HP1 in chromatin recruitment results in a tripartite interaction that may span neighboring nucleosomes and illustrates how the 'histone-code' is interpreted by a combination of multivalent effector-chromatin interactions.
Combinatorial readout of histone H3 modifications specifies localization of ATRX to heterochromatin.,Eustermann S, Yang JC, Law MJ, Amos R, Chapman LM, Jelinska C, Garrick D, Clynes D, Gibbons RJ, Rhodes D, Higgs DR, Neuhaus D Nat Struct Mol Biol. 2011 Jun 12. doi: 10.1038/nsmb.2070. PMID:21666677
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.