The role of cell adhesion in the synchronization and orientation of polarization in 8-cell mouse blastomeres.

A detailed investigation into the activity of the homotypic, Ca2+-dependent cell-cell adhesion system (CDS) in the early mouse embryo has revealed its involvement in the synchronizing of the time of polarization of 8-cell blastomeres, and the orienting of the axis of polarization. Since polarization marks an important and early event in the process of cell diversification in the mouse embryo, it is concluded that the CDS provides an important component of the system by which the temporal and spatial elements of normal development are integrated.