3TU4: Crystal Structure of the Sir3 BAH Domain in Complex With a Nucleosome Core Particle

Citation:
Abstract
Gene silencing is essential for regulating cell fate in eukaryotes. Altered chromatin architectures contribute to maintaining the silenced state in a variety of species. The silent information regulator (Sir) proteins regulate mating type in Saccharomyces cerevisiae. One of these proteins, Sir3, interacts directly with the nucleosome to help generate silenced domains. We determined the crystal structure of a complex of the yeast Sir3 BAH (bromo-associated homology) domain and the nucleosome core particle at 3.0 angstrom resolution. We see multiple molecular interactions between the protein surfaces of the nucleosome and the BAH domain that explain numerous genetic mutations. These interactions are accompanied by structural rearrangements in both the nucleosome and the BAH domain. The structure explains how covalent modifications on H4K16 and H3K79 regulate formation of a silencing complex that contains the nucleosome as a central component.
PDB ID: 3TU4Download
MMDB ID: 95273
PDB Deposition Date: 2011/9/15
Updated in MMDB: 2011/12 
Experimental Method:
x-ray diffraction
Resolution: 3  Å
Source Organism:
Saccharomyces cerevisiae S288C
Similar Structures:
Biological Unit for 3TU4: dodecameric; determined by author
Molecular Components in 3TU4
Label Count Molecule
Proteins (10 molecules)
2
Histone H3.2
(Gene: hist2h3c.L)
Molecule annotation
2
Histone H4
(Gene: hist1h4a.L)
Molecule annotation
2
Histone H2A
Molecule annotation
2
Histone H2B 1.1
(Gene: hist1h2bj.S)
Molecule annotation
2
Regulatory Protein Sir3
(Gene: SIR3)
Molecule annotation
Nucleotides(2 molecules)
1
DNA (146-mer)
Molecule annotation
1
DNA (146-mer)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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