Direct continuities between cisternae at different levels of the Golgi complex in glucose-stimulated mouse islet beta cells.

ABSTRACT: Direct continuity between the membranes of cisternae in the Golgi complex in mammalian cells rarely has been observed; when seen, its documentation has been equivocal. Here we have used dual-axis electron microscope tomography to examine the architecture of the Golgi in three dimensions at approximately 6-nm resolution in rapidly frozen, freeze-substituted murine cells that make and secrete insulin in response to glucose challenge. Our data show three types of direct connections between Golgi cisternae that are normally distinct from one another. These connections all "bypass" interceding cisternae. We propose that when pancreatic beta cells are stimulated to synthesize and secrete insulin rapidly in vivo, such connections provide a continuous lumen that facilitates the rapid transit of la

SUBMITTER: Marsh BJ 

PROVIDER: S-EPMC397423 | biostudies-literature | 2004 Apr

REPOSITORIES: biostudies-literature