Cohesin is a chromosome-bound, multisubunit adenosine triphosphatase complex. After loading onto chromosomes, it generates loops to regulate chromosome functions. It has been suggested that cohesin organizes the genome through loop extrusion, but direct evidence is lacking. Here, we used single-molecule imaging to show that the recombinant human cohesin-NIPBL complex compacts both naked and nucleosome-bound DNA by extruding DNA loops. DNA compaction by cohesin requires adenosine triphosphate (ATP) hydrolysis and is force sensitive. This compaction is processive over tens of kilobases at an average rate of 0.5 kilobases per second. Compaction of double-tethered DNA suggests that a cohesin dimer extrudes DNA loops bidirectionally. Our results establish cohesin-NIPBL as an ATP-driven molecular machine capable of loop extrusion.

The Hippo pathway has been implicated in suppressing tissue overgrowth and tumor formation by restricting the oncogenic activity of YAP. However, transcriptional regulators that inhibit YAP activity have not been well studied. Here, we uncover clinical importance for VGLL4 in gastric cancer suppression and find that VGLL4 directly competes with YAP for binding TEADs. Importantly, VGLL4's tandem Tondu domains are not only essential but also sufficient for its inhibitory activity toward YAP. A peptide mimicking this function of VGLL4 potently suppressed tumor growth in vitro and in vivo. These findings suggest that disruption of YAP-TEADs interaction by a VGLL4-mimicking peptide may be a promising therapeutic strategy against YAP-driven human cancers.

As a ring-shaped adenosine triphosphatase (ATPase) machine, cohesin organizes the eukaryotic genome by extruding DNA loops and mediates sister chromatid cohesion by topologically entrapping DNA. How cohesin executes these fundamental DNA transactions is not understood. Using cryo–electron microscopy (cryo-EM), we determined the structure of human cohesin bound to its loader NIPBL and DNA at medium resolution. Cohesin and NIPBL interact extensively and together form a central tunnel to entrap a 72–base pair DNA. NIPBL and DNA promote the engagement of cohesin’s ATPase head domains and ATP binding. The hinge domains of cohesin adopt an “open washer” conformation and dock onto the STAG1 subunit. Our structure explains the synergistic activation of cohesin by NIPBL and DNA and provides insight into DNA entrapment by cohesin.