Wdr26 interacts with other Gid proteins to regulate nuclear condensation. (A) Schematic of protein pull-down assays and mass spectrometry pipeline. (B) The Gid proteins pulled down by Wdr26-FLAG or Gid8-FLAG in erythroid-like differentiating MEL cells. (C) mRNA expression of Gid genes in DMSO-induced MEL cells (left) and in R2-R5 subpopulations of primary mouse erythroblasts²³  (right). (D) mRNA expression of GID genes in terminally differentiating human erythroblasts.²⁴  Stages of erythroblasts shown are proerythroblast (ProE), early (EBaso) and late (LBaso) basophilic erythroblast, polychromatic erythroblast (Poly), and orthochromatic erythroblast (Ortho). (E-F) Validation of the interaction between Wdr26 and (E) Ranbp10 or (F) Gid8 in erythroid-induced MEL cells. (G) Western blot analysis revealed presence of Wdr26 in both the cytoplasm and nucleus of MEL cells. Lamin A/C and Tubulin were used as controls for subcellular fractionation. (H) Treatment of leptomycin B (60 nM) enhanced the localization of FLAG-Wdr26 in the nucleus of differentiating MEL cells. Scale bars, 5 µm. (I) Ranbp10, Rmnd5a, and Gid8 localized to the cytosol and nucleus; their nuclear localization was enhanced in the presence of 60 nM leptomycin B. (J) Knockout of Ranbp10, Gid8, or Rmnd5a in MEL cells resulted in increased nuclear size during erythroid-like differentiation. At least 100 cells were quantified for each clone. **P < .01. (K) Western analysis of nuclear proteins in DMSO-induced MEL cells that are deficient of Ranbp10, Gid8, or Rmnd5a.