TY - JOUR T1 - Phase separation induced by cohesin SMC protein complexes JF - bioRxiv DO - 10.1101/2020.06.13.149716 SP - 2020.06.13.149716 AU - Je-Kyung Ryu AU - Celine Bouchoux AU - Hon Wing Liu AU - Eugene Kim AU - Masashi Minamino AU - Ralph de Groot AU - Allard J. Katan AU - Andrea Bonato AU - Davide Marenduzzo AU - Davide Michieletto AU - Frank Uhlmann AU - Cees Dekker Y1 - 2020/01/01 UR - http://biorxiv.org/content/early/2020/06/14/2020.06.13.149716.abstract N2 - Cohesin is a key protein complex that organizes the spatial structure of chromosomes during interphase. Here, we show that yeast cohesin shows pronounced clustering on DNA in an ATP-independent manner, exhibiting all the hallmarks of phase separation. In vitro visualization of cohesin on DNA shows DNA-cohesin clusters that exhibit liquid-like behavior. This includes mutual fusion and reversible dissociation upon depleting the cohesin concentration, increasing the ionic strength, or adding 1,6-hexanediol, conditions that disrupt weak interactions. We discuss how bridging-induced phase separation can explain the DNA-cohesin clustering through DNA-cohesin-DNA bridges. We confirm that, in vivo, a fraction of cohesin associates with chromatin in yeast cells in a manner consistent with phase separation. Our findings establish that SMC proteins can exhibit phase separation, which has potential to clarify previously unexplained aspects of in vivo SMC behavior and constitute an additional principle by which SMC complexes impact genome organization.One sentence summary Yeast cohesin complex is observed to phase separate with DNA into liquid droplets, which it accomplishes by ATP-independent DNA bridging.Competing Interest StatementThe authors have declared no competing interest. ER -