Fig 4.

Integrator 9 binds to Integrator 11 through a region at the extreme C terminus. (A) Schematic of IntS9 deletion mutants used to test interaction with IntS11. (B) Western blot analysis of lysates from cells cotransfected with HA-tagged IntS9 fragments and full-length IntS11. Upper panel, relative expression of IntS9 fragments assessed with an anti-HA Western blot; lower panel, relative pulldown efficiency of each HA-tagged IntS9 deletion mutant determined by assessing the amount of myc-IntS11 present in the anti-HA immunoprecipitates. (C) Schematic of C-terminal fragments fused to HA-GFP spanning the 161 amino acids of IntS9. (D) Western blot analysis measuring the relative efficiencies of the HA-GFP IntS9 fragments in pulling down myc-tagged IntS11.