Fig. 5

Loss of MBNL1 leads to valve dysmorphia in the fetal heart. Three-dimensional representations of the pulmonary valve at E19.5 reconstructed from optical sections of a representative wild type (a) and three different Mbnl1 ^∆E3/∆E3 (b) hearts imaged using optical coherence tomography. Videos of the optical sections and reconstructions of the wild type heart in (a) and the leftmost of the Mbnl1 ^∆E3/∆E3 hearts in (b) are shown in Additional file 5: Movie S3 and Additional file 6: Movie S4, respectively. Representative high magnification views of the pulmonary (c, d), aortic (f, g), mitral (i, j), and tricuspid (l, m) valves of E18.5 wild type (c, d, i, l) and Mbnl1 ^∆E3/∆E3 (d, g, j, m) heart sections stained with hematoxylin and eosin. Yellow asterisks indicate eosinophilic tissue connecting the valve leaflets to the vessel or chamber wall. Nearby sections through the pulmonary (e), aortic (h), mitral (k), and tricuspid (n) valves of the Mbnl1 ^∆E3/∆E3 hearts shown in (d, g, j, m) were stained with Movat’s pentachrome stain. Scale bars in panels C-N represent 100 μm