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Additional file 2.

The ring-shaped cohesin complex participates in various biological processes including DNA replication and repair, cell cycle progression, gene expression, and three-dimensional organization of the genome. Despite these important roles, little is known regarding the mechanisms that facilitate loading, translocation, and unloading of this complex. The prominent model involves loading of the complex by NIPBL and unloading by WAPL. This model has been challenged, however, by recent reports which provide evidence for previously unappreciated roles of NIPBL and WAPL. For example, NIPBL has been shown to be required for active extrusion of DNA loops by the cohesin complex and some reports provide conflicting evidence on the molecular role of WAPL. Moreover, various recent reports have identified previously unknown binding partners of cohesin. Therefore, additional unrecognized binding partners may exist and affect the localization and/or function of the complex. Finally, new structural evidence suggests that the cohesin ring adopts complex orientations in the nucleus which were not previously identified, which may imply that specific domains of the proteins involved have important roles in the function of the complex or its association with DNA. Utilizing biochemistry, molecular biology, and genomics, this work evaluates the molecular determinants of cohesin localization and function. We introduce a previously unrecognized binding partner of the cohesin complex, WIZ. Loss of WIZ results in genome-wide alterations in cohesin localization and changes in gene expression and genome organization. We demonstrate that WIZ regulates cohesin localization in a manner distinct from the canonical unloader WAPL, and in a manner distinct from its previously identified binding partner G9a. Additional data demonstrate that the cohesin accessory proteins STAG1 and STAG2 have largely redundant roles in the control of cohesin localization but have somewhat unique roles in regulating gene expression. Finally, we analyze the importance of the hinge domain of the cohesin complex by mutating a residue within the SMC1A subunit. We find that disruption of the hinge domain results in genome-wide loss of cohesin binding, widespread changes in gene expression, and loss of enhancer-promoter loops. In all, the work herein advances our understanding of the molecular determinants of cohesin localization and function.

Additional file 2. Additional figures and corresponding legends for each complimentary main text figure (S1, S2, S3, and S4).

Additional file 1: Table S1. Accession numbers of data used in this study. Summary table of the datasets used in this study including antibody product number, genotypes, factor accession numbers, as well as background accession numbers.