Raman maps of <i>C. intestinalis</i> embryos from 2-cell to tailbud stage.

<p>(A–J) Confocal 3D (from 2-cell to 112-cell stages) and section images from dorsal (gastrula and neurula stages) or side views (tailbud stage) of <i>C. intestinalis</i> embryos stained with phalloidin (white). Images show the location of differentiated muscle (green) and endoderm (yellow) within the embryo. (A’ –J’ and A’’ –J’’) Bright-field (left) and Raman maps in a rainbow scale (right) constructed from the intensity of single bands at the 1002 (A’ –J’) and 1526 (A’’ –J’’) cm⁻¹ at each stage. Because the <i>C. intestinalis</i> embryo is bilaterally symmetrical, Raman maps of only half of the embryo are represented. Red line in maps from 16-cell to 112-cell stage represents the presumed cell border. To identify the cell boundary, the bright-field images and Raman maps constructed from Raman bands of CellMask (group III) were used. In addition to the Raman band at 1526 cm⁻¹, Raman maps constructed from other bands of group II (Fig. 2 and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0071739#pone-0071739-t001" target="_blank">Table 1</a>) also represented similar distribution of high-intensity spots (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0071739#pone.0071739.s003" target="_blank">Fig. S3</a>). Abbreviations: A, Anterior; P, Posterior; L, Left; R, Right; a, animal; v, vegetal; Mus, muscle; Endo, endoderm. Scale bar: 20 μm.