Details of juveniles 5 min to 10 min after the completion of inversion (early post-inversion stage). cLSM, SEM and LM images of intact or fragmented juveniles and LM and TEM images of physical cross-sections. (A) Midsagittal cLSM optical cross-section of a juvenile showing the localization of F-actin (red) using phalloidin-TRITC (see Figure 5E1 for an overview). (B) Midsagittal cLSM optical cross-section of a juvenile showing the localization of both F-actin (red) and nuclei (blue) with a phalloidin-TRITC/DAPI overlay (see Figure 5E3 for an overview). (C) SEM view of the cell monolayer from outside the spheroid (see Figures 3H and 4H for an overview); arrowheads point to some of the flagella. (D) Slanted SEM side view of cells (fragmented juvenile); arrowheads point to the flagella. (E) LM image of a physical midsagittal cross-section (see Figures 3H and 4H for an overview); arrowheads point to some of the flagella. (F) SEM side view of cells of the cell monolayer (fragmented juvenile); arrowheads point to the CBs (see Figures 3H and 4H for an overview). (G) TEM image of a physical midsagittal cross-section of the cell monolayer showing some of the zones of the ECM (see Figures 3H and 4H for an overview); flagellar zone (FZ), boundary zone (BZ), cellular zone (CZ) and ECM zones and subzones are described in  and . (H to J) LM side view of a juvenile inside the intact parental spheroid. (H, I) Arrowheads point to minor dents that quickly appear and disappear immediately after inversion. (J) After the short period of denting, the embryos remain spherical. Scale bars: (A, B, E) 10 μm; (C) 3 μm; (D, F) 5 μm; (G) 1 μm; (H, I, J) 20 μm. BZ: boundary zone; CB: cytoplasmic bridge; CZ, cellular zone; cLSM: confocal laser scanning microscopy; DAPI: 4',6-diamidino-2-phenylindole dihydrochloride; ECM: extracellular matrix; F-actin: filamentous actin; FZ: flagellar zone; LM: light microscopy; SEM: scanning electron microscopy; TEM: transmission electron microscopy; TRITC: tetramethylrhodamine B isothiocyanate.
Höhn and Hallmann BMC Biology 2011 9:89 doi:10.1186/1741-7007-9-89