Structure of the chromatin remodelling enzyme Chd1 bound to a ubiquitinylated nucleosome
- University of Dundee, United Kingdom
- University of St Andrews, United Kingdom
Abstract
ATP-dependent chromatin remodelling proteins represent a diverse family of proteins that share ATPase domains that are adapted to regulate protein-DNA interactions. Here we present structures of the Saccharomyces cerevisiae Chd1 protein engaged with nucleosomes in the presence of the transition state mimic ADP-beryllium fluoride. The path of DNA strands through the ATPase domains indicates the presence of contacts conserved with single strand translocases and additional contacts with both strands that are unique to Snf2 related proteins. The structure provides connectivity between rearrangement of ATPase lobes to a closed, nucleotide bound state and the sensing of linker DNA. Two turns of linker DNA are prised off the surface of the histone octamer as a result of Chd1 binding, and both the histone H3 tail and ubiquitin conjugated to lysine 120 are re-orientated towards the unravelled DNA. This indicates how changes to nucleosome structure can alter the way in which histone epitopes are presented.
Data availability
The EM structures generated have been deposited in EMDB and PDB under the accession codes EMD-4318, PDB 6FTX, EMD-4336, PDB 6G0L.
Article and author information
Author details
Funding
Wellcome (95062)
- Ramasubramanian Sundaramoorthy
- Amanda L Hughes
- Hassane El-Mkami
- David G Norman
- Tom Owen-Hughes
European Molecular Biology Organization (ALTF 380-2015)
- Amanda L Hughes
Wellcome (94090)
- Ramasubramanian Sundaramoorthy
- Amanda L Hughes
- Hassane El-Mkami
- David G Norman
- Tom Owen-Hughes
Wellcome (99149)
- Ramasubramanian Sundaramoorthy
- Amanda L Hughes
- Hassane El-Mkami
- David G Norman
- Tom Owen-Hughes
Wellcome (97945)
- Ramasubramanian Sundaramoorthy
- Amanda L Hughes
- Hassane El-Mkami
- David G Norman
- Tom Owen-Hughes
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Sundaramoorthy et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structure of the chromatin remodelling enzyme Chd1 bound to a ubiquitinylated nucleosome
eLife 7:e35720.
https://doi.org/10.7554/eLife.35720
Further reading
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