Structural basis for Scc3-dependent cohesin recruitment to chromatin
Abstract
The cohesin ring complex is required for numerous chromosomal transactions, including sister chromatid cohesion, DNA damage repair and transcriptional regulation. How cohesin engages its chromatin substrate has remained an unresolved question. We show here, by determining a crystal structure of the budding yeast cohesin HEAT-repeat subunit Scc3 bound to a fragment of the Scc1 kleisin subunit and DNA, that Scc3 and Scc1 together form a composite DNA interaction module. The Scc3-Scc1 subcomplex engages double-strand DNA through a conserved, positively charged surface. We demonstrate that this conserved domain is required for DNA binding by Scc3-Scc1 in vitro, as well as for the enrichment of cohesin on chromosomes and for cell viability. These findings suggest that the Scc3-Scc1 DNA-binding interface plays a central role in the recruitment of cohesin complexes to chromosomes and therefore for cohesin to faithfully execute its functions during cell division.
Data availability
Diffraction data have been deposited in PDB under the accession code 6H8Q.
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Diffraction data fromPublicly available at the RCSB Protein Data Bank (accession no: 6H8Q).
Article and author information
Author details
Funding
European Molecular Biology Labratory
- Yan Li
- Kyle Muir
- Matthew W Bowler
- Jutta Metz
- Christian H Haering
- Daniel Panne
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Li 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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