Figure 4. Cohesin–loader interaction analysis.

(a) Diagram indicating intermolecular crosslinks (n=30) between cohesin subunits and Scc2–Scc4. Grey boxes are structured domains of cohesin and Scc2–Scc4 (Smc-coiled coils are not indicated). Red crosslinks indicate interaction between GD0 and cohesin. Crosslinks that are consistent with the published human cohesin crosslinks¹² are in blue. Crosslinks that are consistent with published Smc3–Scc1N and Scc2N–Scc4 crystal structures⁷,³² are in yellow. Crosslinks that are consistent with both the published human cohesin crosslinks and crystal structures are in green. A crosslink that would require a conformation change in the loader to occur for distance restraints to be satisfied is in orange. Positions of Scc2 mutations I–IV, DNA-entry/exit gate⁹ and the documented Pds5-binding sites¹²,²⁸,²⁹,³⁸ are marked. (b) Silver-stain gel showing glycerol gradient fractions of GD0 domain. M indicates protein marker. (c) Silver-stain gel showing glycerol gradient fractions of cohesin. (d) Over-stained silver-stain gel showing glycerol gradient fractions of cohesin. (e) Silver-stain gel showing glycerol gradient fractions of S. cerevisiae cohesin plus GD0 domain. (f) Over-stained silver-stain gel showing glycerol gradient fractions of cohesin plus GD0 with cohesin-bound GD0 being more visible.