Figure 4

Subcellular localization of cubilin, amnionless and intrinsic factor in ileal enterocytes. A shows a confocal image from a section of a Cubn^{+/del exon 1–6;EGFP} mouse ileum labeled with anti-cubilin. B is a merged image of the section of Cubn^{+/del exon 1–6;EGFP} mouse intestine shown in A labeled with anti-cubilin and anti-EGFP together with Draq5 nuclear staining (blue). Arrowheads in A and B point to anti-cubilin label on the apical surfaces of enterocytes. Arrows in A and B point to anti-cubilin label in the cytoplasm of anti-EGFP-positive enterocytes. Asterisks in B indicate goblet cells devoid of anti-EGFP labeling and lacking apical anti-cubilin labeling. C shows a confocal image from a section of a Cubn^{+/del exon 1–6;EGFP} mouse ileum labeled with anti-amnionless. D is a merged image of the section of Cubn^{+/del exon 1–6;EGFP} mouse intestine in C showing cubilin-EGFP expression together with Draq5 nuclear labeling. Arrowheads in C and D point to anti-amnionless label on the apical surfaces of enterocytes. Arrows in C and D point to anti-amnionless label in the cytoplasm of EGFP-positive enterocytes. E shows a confocal image from a section of a Cubn^{+/del exon 1–6;EGFP} mouse ileum labeled with anti-intrinsic factor (IF). F is a merged image of the section of Cubn^{+/del exon 1–6;EGFP} mouse intestine in E together with cubilin-EGFP expression. Arrowheads in E point to anti-intrinsic factor IgG-reactive material present on the surfaces of both anti-EGFP-positive and anti-EGFP-negative enterocytes. G shows a confocal image from a section of a wildtype mouse ileum labeled with anti-intrinsic factor. H is a merged image of the section of the wildtype mouse intestine shown in G together with the image from the EGFP channel.