Implantation and the placenta: key pieces of the development puzzle

JC Cross, Z Werb, SJ Fisher - Science, 1994 - science.org
JC Cross, Z Werb, SJ Fisher
Science, 1994science.org
The mammalian embryo cannot develop without the placenta. Its specialized cells
(trophoblast, endoderm, and extraembryonic mesoderm) form early in development. They
attach the embryo to the uterus (implantation) and form vascular connections necessary for
nutrient transport. In addition, the placenta redirects maternal endocrine, immune, and
metabolic functions to the embryo's advantage. These complex activities are sensitive to
disruption, as shown by the high incidence of early embryonic mortality and pregnancy …
The mammalian embryo cannot develop without the placenta. Its specialized cells (trophoblast, endoderm, and extraembryonic mesoderm) form early in development. They attach the embryo to the uterus (implantation) and form vascular connections necessary for nutrient transport. In addition, the placenta redirects maternal endocrine, immune, and metabolic functions to the embryo's advantage. These complex activities are sensitive to disruption, as shown by the high incidence of early embryonic mortality and pregnancy diseases in humans, as well as the numerous peri-implantation lethal mutations in mice. Integration of molecular and developmental approaches has recently produced insights into the molecules that control these processes.
AAAS