dc.contributor.author | Denis, H | fr_FR |
dc.date.accessioned | 2012-07-11T08:42:45Z | |
dc.date.available | 2012-07-11T08:42:45Z | |
dc.date.issued | 1997 | fr_FR |
dc.identifier.citation | Denis, H, L'origine de la gastrulation, Med Sci (Paris), 1997, Vol. 13, N° 12; p.1503-16 | fr_FR |
dc.identifier.issn | 1958-5381 | fr_FR |
dc.identifier.uri | http://hdl.handle.net/10608/591 | |
dc.description.abstract | Gastrulation is a crucial developmental event occurring in all Metazoa. A simple form of gastrulation can be observed in some diploblastic Metazoa. The egg of these animals gives rise to a blastula, which is a hollow, single-layer sphere of epithelial cells. The blastula transforms into gastrula by a progressive change in cell shape known as invagination. A particular region of the epithelium forms a depression in the blastula. The depression later deepens into a secondary cavity which communicates with the exterior by a single opening called the blastopore. This results in a concentric arrangement of the embryonic cells into two layers surrounding a digestive cavity. The non-invaginating cells form the ectodermal layer, whereas the invaginating cells form the endodermal layer. Invagination is thought to be the basic process by which a blastula-like ancestral organism evolved into a two-layer, gastrula-like animal. Conceivably, this transformation can be ascribed to a cytoskeleton-driven mechanism causing the presumptive endodermal cells to modify their shape so as to invaginate. This evolutionary scheme implies that endoderm played a more important role than ectoderm in embryogenesis of primitive Metazoa. A similar trend can be discerned in early development of present-day animals: the invaginating region functions as a major morphogenetic territory in the embryo because it contains several gene products that directly or indirectly trigger gastrulation. [References: 65] | en |
dc.language.iso | fr | fr_FR |
dc.publisher | Masson Périodiques, Paris | fr_FR |
dc.rights | Article en libre accès | fr |
dc.rights | Médecine/Sciences - Inserm - SRMS | fr |
dc.source | M/S. Médecine sciences [revue papier, ISSN : 0767-0974], 1997, Vol. 13, N° 12; p.1503-16 | fr_FR |
dc.title | L'origine de la gastrulation | fr |
dc.title.alternative | The origin of gastrulation. | fr_FR |
dc.type | Article | fr_FR |
dc.contributor.affiliation | L'Universite Pierre-et-Marie-Curie, Centre de Genetique Moleculaire, Cnrs, Avenue de la Terrasse, 91198 Gif-sur Yvette Cedex; France. | - |
dc.identifier.doi | 10.4267/10608/591 | |