PDBsum entry: 1dz1

Chromatin structure

PDB id: 1dz1

Contents

Protein chains

70 a.a. *

* Residue conservation analysis

PDB id:

1dz1

Name:

Chromatin structure

Title:

Mouse hp1 (m31) c terminal (shadow chromo) domain

Structure:

Modifier 1 protein. Chain: a, b. Fragment: shadow chromo domain, residues 104-171. Synonym: m31, hp1 beta, momod1, heterochromatin protein 1. Engineered: yes

Source:

Mus musculus. House mouse. Organism_taxid: 10090. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

16 models

Authors:

S.V.Brasher,B.O.Smith,R.H.Fogh,D.Nietlispach,A.Thiru, P.R.Nielsen,R.W.Broadhurst,L.J.Ball,N.Murzina,E.D.Laue

Key ref:

S.V.Brasher et al. (2000). The structure of mouse HP1 suggests a unique mode of single peptide recognition by the shadow chromo domain dimer. EMBO J, 19, 1587-1597. PubMed id: 10747027 DOI: 10.1093/emboj/19.7.1587

Date:

11-Feb-00 Release date: 09-Apr-00

Protein chains

P83917  (CBX1_MOUSE) -  Chromobox protein homolog 1

Seq: 185 a.a.

Struc: 70 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

 Gene Ontology (GO) functional annotation 

• Cellular component: nucleus (2 terms)
• Biological process: chromatin assembly or disassembly (1 term)
• Biochemical function: chromatin binding (1 term)

DOI no: 10.1093/emboj/19.7.1587

EMBO J 19:1587-1597 (2000)

PubMed id: 10747027

The structure of mouse HP1 suggests a unique mode of single peptide recognition by the shadow chromo domain dimer.

S.V.Brasher, B.O.Smith, R.H.Fogh, D.Nietlispach, A.Thiru, P.R.Nielsen, R.W.Broadhurst, L.J.Ball, N.V.Murzina, E.D.Laue.

ABSTRACT

The heterochromatin protein 1 (HP1) family of proteins is involved in gene silencing via the formation of heterochromatic structures. They are composed of two related domains: an N-terminal chromo domain and a C-terminal shadow chromo domain. Present results suggest that chromo domains may function as protein interaction motifs, bringing together different proteins in multi-protein complexes and locating them in heterochromatin. We have previously determined the structure of the chromo domain from the mouse HP1beta protein, MOD1. We show here that, in contrast to the chromo domain, the shadow chromo domain is a homodimer. The intact HP1beta protein is also dimeric, where the interaction is mediated by the shadow chromo domain, with the chromo domains moving independently of each other at the end of flexible linkers. Mapping studies, with fragments of the CAF1 and TIF1beta proteins, show that an intact, dimeric, shadow chromo domain structure is required for complex formation.

Selected figure(s)

Figure 1.
Figure 1 Sequences of the chromo domains (A) and the shadow chromo domains (B) from different HP1 proteins, numbered so that they correspond to MOD1. Secondary structure elements observed in MOD1 are shown above the alignments; cylinders represent 3[10] (3–10) or -helices ( 1 and 2), arrows represent -strands and circles indicate -bulges. For each domain the residues that make up the hydrophobic core of a 'subunit' are shaded in yellow and other residues considered important for the structure are shown in green (Gly and Pro). Charged residues in the chromo domain, which are replaced by hydrophobic residues in the shadow chromo domain, are coloured blue (basic) and red (acidic). The red boxes enclose the structured parts of the proteins. Residues that form the dimer interface in the shadow chromo domain are boxed and shaded in grey. Mutations described in this paper are indicated below the alignment. The proteins are, from the top, mouse MOD1/human HP1 (residues 1–81 and 103–185), mouse HP1 (1–80 and 97–173), human HP1 (1–80 and 97–173), human HP1 (1–80 and 106–191), mouse HP1 (1–80 and 106–191), Drosophila melanogaster HP1 (1–84 and 132–206), Drosophila virilis HP1 (1–84 and 139–213) and Schizosaccharomyces pombe SWI6 (59–145 and 252–328).

Figure 6.
Figure 6 Mapping of the MIR peptide binding site on MOD1C. The molecular surface of the MOD1C dimer is shown (A), together with a cartoon of the structure (B). (The view shown is related to that in Figure 3 by 90° rotation about the vertical axis.) Residues for which there are no data are in white, unperturbed residues are in light blue, residues for which there are two cross peaks are in blue, residues for which only one highly perturbed cross peak could be found are in magenta and the most highly perturbed residues are in red. The position of the Trp170 side chain in the binding site is shown in yellow (see the text for details). The surface plot was made using GRASP (Nicholls et al., 1991).

The above figures are reprinted from an Open Access publication published by Macmillan Publishers Ltd: EMBO J (2000, 19, 1587-1597) copyright 2000.

Figures were selected by an automated process.