Transient cytoplasmic bridges among the cells of developing cerebellum: a possible mode of induction for cell differentiation.

In the developing cerebellum of neonate rats, membrane fusions and cytoplasmic bridges were observed between the pre-existing Purkinje cells and the migratory and differentiating granule cells. These ultrastructural specializations of the apposing membranes were seen to be transient in nature, and represented a developmental phenomenon. On the basis of literature available on this type of direct cell-to-cell interaction it is suggested that such transient cytoplasmic bridges may provide induction for differentiation from the pre-existing Purkinje cells to the undifferentiated cells.