Fig. 5

Live imaging of a Xenopus tropicalis embryo; complementarity of the ALMOST approach. Different stages of the same Xenopus tropicalis embryo are shown during neurulation. a Top view from dorsal to ventral side of a stage 12 embryo. b Lateral side view of a. c Same embryo as in a and b after ~ 1.5 h. Stage 14.5 is shown. d Lateral side view of the embryo in c. e Same embryo as in a–d after ~ 2.8 h (relative to a, b). Stage 19 is shown. f Lateral side view of e. g The GFP fluorescence signal of the same embryo is shown after fixation and imaged with a spinning disk. Gray information is the transmitted light signal from the spinning disk. The embryo is a crest3- gfp transgenic line, labeling a subset of neuronal precursor cells. h Zoomed view, comparing e and g. Horizontal section view of the embryo from anterior to posterior and cut open at the line indicated in e and g. As the animals get older, they become more transparent. To demonstrate the complementarity of our approach, we imaged a semitransparent tadpole of stage ~ 50 with ALMOST, with fluorescence OPT, and with transmitted light OPT. i Side view using ALMOST displayed in purple, with more brightness in purple indicating less reflection. Insert is showing a raw reflection image. j Side view using autofluorescence displayed in cyan. Brighter signals indicate stronger autofluorescence. k Side view using transmitted light displayed in green. Brighter signals indicate lower transmission. l Merged view showing the tadpole from the top. m–p Virtual sections through the animal as indicated in l. q Merged side view of i–k, section as indicated in l. The different approaches reveal different aspects of the tadpole. Part of the difference between transmitted light and ALMOST is due to scattering inside the sample. Scale bar = 500 μm in all images. Imaging conditions are summarized in Additional file 20: Table S1