Ultracytochemistry of the secretory pathway in Saccharomyces cerevisiae defies the established pathway model

The molecular and cell biologic data supporting the established model of the intracellular secretory (transport) pathway for glycoproteins in the yeast Saccharomyces cerevisiae have been reviewed and confronted with our electron-cytochemical findings. These in situ findings show a new class of constitutive intracellular conveyors—the coated globules—and also suggest substantial alternatives in the cellular mechanism of the vacuole biogenesis. The controversial question of the Golgi compartment identity in S. cerevisiae is revived.