2005 Trophoblast Research Award Lecture: Defects in the Keratin Cytoskeleton Disrupt Normal Murine Placental Development and Trophoblast Cell Function

The keratin cytoskeleton is present in all trophoblast cell subtypes of the mouse and human placenta and is required to maintain the structural integrity of these cells. Recently, various genetic mouse models have shown that a normal keratin network is necessary for placental development. Keratin-deficiency leads to trophoblast giant cell fragility, breaking the barrier between the conceptus and the maternal blood circulation. Alternatively, keratin aggregation prevents chorioallantoic attachment, a key developmental milestone required for the formation of the labyrinth within the mouse placenta. These models give us insight into cytokeratin function in human trophoblast cell subtypes and suggest that defects in the keratin cytoskeleton may result in intrauterine growth restriction or miscarriage.