Clonal Analysis of Cell Fate During Gastrulation and Early Neurulation in the Mouse

摘要: The foundation of the germ layers and extraembryonic mesoderm from epiblast between 6.5 7.5 days post coitum (p.c.) is accompanied by substantial cell proliferation. It followed during next 24 hours organization major systems embryo such as central nervous system, somites, heart vascular system. Injection in situ a short-term lineage label (horse radish peroxidase) into single cells at 6.7 p.c. analysis descendant clones cultured embryos have been used to trace these processes led following conclusions: (1) There extensive but not indiscriminate mixing onset gastrulation; spread towards primitive streak descendants are there progressively incorporated mesoderm. (2) fate map mouse early stage topologically similar those other vertebrates. (3) Germ clonally distinct before gastrulation, region overlapping boundaries being occupied that will more than one layer. (4) Cranial neurectoderm mainly derived axial immediately anterior embryo, clonal rostrocaudally developing neural tube. Contribution putative floor plate made progenitors some which also contribute notochord