Communication between distinct subunit interfaces of the cohesin complex promotes its topological entrapment of DNA
- University of California, Berkeley, United States
Abstract
Cohesin mediates higher-order chromosome structure. Its biological activities require topological entrapment of DNA within a lumen(s) formed by cohesin subunits. The reversible dissociation of cohesin's Smc3p and Mcd1p subunits is postulated to form a regulated gate that allows DNA entry and exit into the lumen. We assessed gate-independent functions of this interface in yeast using a fusion protein that joins Smc3p to Mcd1p. We show that in vivo all the regulators of cohesin promote DNA binding of cohesion by mechanisms independent of opening this gate. Furthermore, we show that this interface has a gate-independent activity essential for cohesin to bind chromosomes. We propose this interface regulates DNA entrapment by controlling the opening and closing of one or more distal interfaces formed by cohesin subunits, likely by inducing a conformation change in cohesin. Furthermore, cohesin regulators modulate the interface to control both DNA entrapment and cohesin functions after DNA binding.
Data availability
All data generated in this study are included in the manuscript.
Article and author information
Author details
Douglas E Koshland
Funding
National Institutes of Health (1R35 GM-118189-01)
- Douglas E Koshland
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Guacci 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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Communication between distinct subunit interfaces of the cohesin complex promotes its topological entrapment of DNA
eLife 8:e46347.
https://doi.org/10.7554/eLife.46347
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