Cell lineages of the embryo of the nematode Caenorhabditis elegans.

Abstract

Embryogenesis of the free-living soil nematodeCaenorhabditis elegans produces a juvenile having about 550 cells at hatching. We have determined the lineages of 182 cells by tracing the divisions of individual cells in living embryos. An invariant pattern of cleavage divisions of the egg generates a set of stem cells. These stem cells are the founders of six stem cell lineages. Each lineage has its own clock-i.e., an autonomous rhythm of synchronous cell divisions. The rhythms are maintained in spite of extensive cellular rearrangement. The rate and the orientation of the cell divisions of the cell lineages are essentially invariant among individuals. Thus, the destiny of cells seems to depend primarily on their lineage history. The anterior position of the site of origin of the stem cells in the egg relates to the rate of the cell cycle clock, suggesting intracellular preprogramming of the uncleaved egg. We used a technique that allows normal embryogenesis, from the fertilized egg to hatching, outside the parent under a cover glass. The cell lineages reported here were analyzed from tapes of two eggs recording the complete development until the animals started moving inside the egg shell. In addition, embryogenesis was recorded and analyzed in 18 other individuals from fertilization to the 30-(10 cases), the 54-, 60-, 75-, and 87-(3 cases), and the 100-(2 cases) cell stages, respectively. We also analyzed the E-cell lineage in six more individuals to make certain that all 8 E-cells divide in going to 16. After recording was terminated, it was ascertained that, under the cover glass, all 26 animals hatched and moved normally.

Intermediate filaments in Caenorhabditis elegans

“…The intestine is not only responsible for assimilation and digestion of food but also for synthesis and storage of macromolecules such as yolk proteins [McGhee, 2007]. A single cell, the E-blastomere of the eight-cell embryo, gives rise to the entire intestine [Deppe et al, 1978;Sulston et al, 1983;Leung et al, 1999]. The E-cell divides in a stereotypic pattern leading to a defined arrangement of the resulting 20 cells which encircle the intestinal lumen as a series of nine rings referred to as ''ints'' [ Fig.…”

4D retrospective lineage tracing using SPIM for zebrafish organogenesis studies

“…Caenorhabditis elegans was the first to benefit from comprehensive time-lapse imaging at a spatiotemporal resolution sufficient to trace all cells and cell divisions during development, using non-fluorescent differential interference contrast optics [4,5]. This allows an alternative approach for determining the lineage of cells -retrospective lineage analysis.…”

end-1 encodes an apparent GATA factor that specifies the endoderm precursor in Caenorhabditis elegans embryos

“…1; Deppe et al 1978;Sulston et al 1983). Each of the founder cells shows distinct rates of cell division and produces a unique repertoire of differentiated cell types.…”