The localization of non-specific alkaline phosphatase activity during cleavage and blastocyst formation has been investigated in the mouse by electron microscopy. The activity is detectable for the first time at the two-cell stage and is localized on the surface of the interblastomeric plasma membranes and on small cytoplasmic inclusions. It increases in the following stages, predominantly on t...

The localization of non-specific alkaline phosphatase activity during cleavage and blastocyst formation has been investigated in the mouse by electron microscopy. The activity is detectable for the first time at the two-cell stage and is localized on the surface of the interblastomeric plasma membranes and on small cytoplasmic inclusions. It increases in the following stages, predominantly on t...

Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells. They are found in multicellular organisms. In mammals, there are two broad types of stem cells: embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues. In ad...

introduction: stem cell biology has been the subject of much recent discussion. embryonic stem (es) cells, derived from the inner cell mass of the blastocyst stage of early mammalian embryos are expected to become a powerful tool in future regenerative medicine and developmental biology due to their capacity of self-renewal and pluripotency. in the present study, the ultrastructural development...

The timing, spatial distribution and control of cytokeratin assembly during mouse early development has been studied using a monoclonal antibody, TROMA-1, which recognizes a 55,000 Mr trophectodermal cytokeratin (ENDO A). This protein was first detected in immunoblots at the 4-cell stage, and became more abundant at the 16-cell stage and later. Immunofluorescence analysis revealed assembled cyt...