278
L A U R I S A X E N E T A L .
FIG. 19. Radially oriented cells in a young aggregate. Junctional complexes ( T B )
are observable in the apical plasma membrane of the cells. The association of small
vesicles with the plasma membrane is indicated b y arrows. The Golgi apparatus ( G )
lies on the apical side of the nucleus. X 15,000. (From Saxen and Wartiovaara, 1966.)
discerned (Wartiovaara, 1966b) during the aggregation or radial orientation of the cells which could restrict the separation of adjacent cell
membranes.
It was mentioned above that an increase in protein synthesis takes
place during early tubulogenesis and that aggregating cells reflect an
L A U R I S A X E N E T A L .
FIG. 19. Radially oriented cells in a young aggregate. Junctional complexes ( T B )
are observable in the apical plasma membrane of the cells. The association of small
vesicles with the plasma membrane is indicated b y arrows. The Golgi apparatus ( G )
lies on the apical side of the nucleus. X 15,000. (From Saxen and Wartiovaara, 1966.)
discerned (Wartiovaara, 1966b) during the aggregation or radial orientation of the cells which could restrict the separation of adjacent cell
membranes.
It was mentioned above that an increase in protein synthesis takes
place during early tubulogenesis and that aggregating cells reflect an