Click
here to close Hello! We notice that
you are using Internet Explorer, which is not supported by Echinobase
and may cause the site to display incorrectly. We suggest using a
current version of Chrome,
FireFox,
or Safari.
???displayArticle.abstract???
The four small micromeres of the sea urchin embryo contribute only to the coelomic sacs, which produce major components of the adult body plan during postembryonic development. To test the proposition that the small micromeres are the definitive primordial germ cell lineage of the sea urchin, we deleted their 4th cleavage parents, and raised the deleted embryos through larval life and metamorphosis to sexual maturity. Almost all of the experimental animals produced functional gametes, excluding the possibility that the germ cell lineage arises exclusively and obligatorily from descendants of the small micromeres; rather, the germ cell lineage arises during the postembryonic development of the rudiment. A survey of the literature indicates that there is no known case of an embryonic primordial germ cell lineage in a bilaterian species that displays maximal indirect development.
Armstrong,
Cell-cell interactions regulate skeleton formation in the sea urchin embryo.
1993, Pubmed,
Echinobase
Armstrong,
Cell-cell interactions regulate skeleton formation in the sea urchin embryo.
1993,
Pubmed
,
Echinobase Buss,
Evolution, development, and the units of selection.
1983,
Pubmed Cameron,
Lineage and fate of each blastomere of the eight-cell sea urchin embryo.
1987,
Pubmed
,
Echinobase Cameron,
Macromere cell fates during sea urchin development.
1991,
Pubmed
,
Echinobase Davidson,
Origin of bilaterian body plans: evolution of developmental regulatory mechanisms.
1995,
Pubmed Davidson,
Lineage-specific gene expression and the regulative capacities of the sea urchin embryo: a proposed mechanism.
1989,
Pubmed
,
Echinobase Ettensohn,
Cell lineage conversion in the sea urchin embryo.
1988,
Pubmed
,
Echinobase Gardner,
Clonal analysis of X-chromosome inactivation and the origin of the germ line in the mouse embryo.
1985,
Pubmed Ginsburg,
Primordial germ cells in the mouse embryo during gastrulation.
1990,
Pubmed Illmensee,
Transplantation of posterior polar plasm in Drosophila. Induction of germ cells at the anterior pole of the egg.
1974,
Pubmed Khaner,
Interactions of different vegetal cells with mesomeres during early stages of sea urchin development.
1991,
Pubmed
,
Echinobase Lawson,
Clonal analysis of the origin of primordial germ cells in the mouse.
1994,
Pubmed Leahy,
A large-scale laboratory maintenance system for gravid purple sea urchins (Strongylocentrotus purpuratus).
1978,
Pubmed
,
Echinobase Leahy,
Laboratory culture of Strongylocentrotus purpuratus adults, embryos, and larvae.
1986,
Pubmed
,
Echinobase McClay,
Regulative capacity of the archenteron during gastrulation in the sea urchin.
1996,
Pubmed
,
Echinobase Pehrson,
The fate of the small micromeres in sea urchin development.
1986,
Pubmed
,
Echinobase Ransick,
Micromeres are required for normal vegetal plate specification in sea urchin embryos.
1995,
Pubmed
,
Echinobase Ransick,
A complete second gut induced by transplanted micromeres in the sea urchin embryo.
1993,
Pubmed
,
Echinobase Seydoux,
Soma-germline asymmetry in the distributions of embryonic RNAs in Caenorhabditis elegans.
1994,
Pubmed Sulston,
The embryonic cell lineage of the nematode Caenorhabditis elegans.
1983,
Pubmed West,
Embryology of the house fly, Musca domestica (Diptera: Muscidae), to the blastoderm stage.
1968,
Pubmed