Biomaterial Database

The formation of the embryonic mesoderm in the early post-implantation mouse embryo. 1981

R E Poelmann

The formation of the mesoderm in early post-implantation mouse embryos is described and analysed. The outgrowth of the mesoderm was found to depend on the changes in the shape of the embryonic ectoderm, which lead to a relative displacement of the primitive streak in the caudal direction. The primitive streak deposits its cells laterally in the case of the lateral mesoderm, and medially in the case of the headprocess. In doing so, the primitive streak leaves a trail of mesoderm cells. This means that mesoderm cells do not migrate actively from the caudally located primitive streak towards more frontal positions in the embryo. This is confirmed by the results of scanning electron microscopy, which revealed that mesoderm cells show no polarity at all in the caudofrontal direction. In may therefore be concluded that these cells probably do not migrate. Studies on the cell-cycle parameters of the embryonic ectoderm, showed that mesoderm cells-to-be are probably recruited not only from the proliferation zone, but also from the lateral ectoderm. It is postulated that the lateral ectoderm gives rise, via the largest part of the primitive streak, to most of the mesoderm cells, whereas the proliferation zone gives rise to the head-process mesoderm, via the anterior part of the primitive streak.

UI	MeSH Term	Description	Entries
D008648	Mesoderm	The middle germ layer of an embryo derived from three paired mesenchymal aggregates along the neural tube.	Mesenchyme,Dorsal Mesoderm,Intermediate Mesoderm,Lateral Plate Mesoderm,Mesenchyma,Paraxial Mesoderm,Dorsal Mesoderms,Intermediate Mesoderms,Lateral Plate Mesoderms,Mesenchymas,Mesoderm, Dorsal,Mesoderm, Intermediate,Mesoderm, Lateral Plate,Mesoderm, Paraxial,Mesoderms, Dorsal,Mesoderms, Intermediate,Mesoderms, Lateral Plate,Mesoderms, Paraxial,Paraxial Mesoderms,Plate Mesoderm, Lateral,Plate Mesoderms, Lateral
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D002453	Cell Cycle	The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.	Cell Division Cycle,Cell Cycles,Cell Division Cycles,Cycle, Cell,Cycle, Cell Division,Cycles, Cell,Cycles, Cell Division,Division Cycle, Cell,Division Cycles, Cell
D002465	Cell Movement	The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.	Cell Migration,Locomotion, Cell,Migration, Cell,Motility, Cell,Movement, Cell,Cell Locomotion,Cell Motility,Cell Movements,Movements, Cell
D004475	Ectoderm	The outer of the three germ layers of an embryo.	Apical Ectodermal Ridge,Apical Ectodermal Ridges,Ectodermal Ridge, Apical,Ectoderms
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus