Cytokinetic furrowing of the membranes of dividing cells is clearly seen. Also apparent are the migration and ingression of external cells into the embryo interior during the process of gastrulation. The pronounced brightening of the dying cell is most likely due to loss of cell membrane integrity. A programmed cell death occurring within the same embryo from Fig. 1. Some specialized cell types showed atypical labeling which included more than just the outer plasma membrane of the cell.
Intestinal precursors acquire bright cytoplasmic spots.
Arrowhead indicates the fusion of two cells within the dorsal hypodermis. Unlike confocal recordings, no conspicuous photobleaching was seen in these data sets, and development proceeded normally over the entire imaged time span. Recently colleagues have extended this approach to the systematic study of morphogenetic mutations, imaging fields of up to 20 transgenic embryos simultaneously. Timecourse follows the embryo from the onset of fluorescent transgene expression through hypodermal differentiation, migration, enclosure, and cell fusion. The initial success we have had with two fluorescent markers in C. elegans embryos makes us optimistic about extension of this system to the study of other organelles, molecules and signals in development through the use of alternative fluorescent probes.