PCBP1 deletion does not suppress ferroportin expression in differentiated enteroids. (A) Expression of PCBP1 and ferroportin in differentiated WT enteroids. Undifferentiated enteroids on the left, differentiated on the right. Enteroids were fixed and analyzed by indirect immunofluorescence. Proliferation marker Ki67 (red, top panel), FPN (red, bottom panel), PCBP1 (green) and DAPI (blue) are shown. Bar = 50 μm. (B) Expression of key iron homeostatic proteins in differentiated enteroids. Enteroids prepared as in panel A were analyzed for DMT1, Ki67, ferritin (Ftn), and transferrin receptor 1 (TfR) as indicated. DAPI staining in blue. Higher magnification and merged images show distinct subcellular localizations. Bar = 10 μm. (C) Depletion of PCBP1 does not affect FPN expression in the enteroids. PCBP1 depletion was induced with 4-OH tamoxifen in differentiating enteroids from PCBP1^fl/fl, TG vil-Cre^ERT2 mice. Indirect immunofluorescence for PCBP1, FPN, and DAPI in WT (no tamoxifen) and ΔPCBP1 (tamoxifen) is shown. Quantitation of fluorescent images is shown below in panel F. (D) No change in basolateral localization of ferroportin in PCBP1-depleted enteroids. Higher magnification images of FPN from central sections in WT and ΔPCBP1 enteroids. Bar = 20 μm. (E) Efficient deletion of PCBP1 in differentiated enteroids. Enteroids treated as in panel C were analyzed by qPCR.