Pancreatic plasma membranes: promiscuous partners in membrane fusion.
We have developed a system in which the fusion of pancreatic plasma membranes with zymogen granules can be studied in vitro. We show here that pancreatic plasma membranes fuse not only with pancreatic zymogen granules but also with parotid secretory granules. In contrast, parotid membranes fuse only with parotid granules and not with pancreatic granules. The extent of fusion is insensitive to Ca2+ for all combinations of plasma membranes and granules. Guanosine 5'-[gamma-thio]triphosphate (GTP[S]), on the other hand, stimulates fusion of pancreatic membranes with both pancreatic granules and parotid granules, but inhibits fusion between parotid membranes and parotid granules.
Lee
E G
EG
Department of Pharmacology, University of Cambridge, U.K.
Marciniak
S J
SJ
MacLean
C M
CM
Edwardson
J M
JM
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology*; D003594:Cytoplasmic Granules / Q000502:physiology*; D004792:Enzyme Precursors / Q000502:physiology; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D008561:Membrane Fusion / Q000187:drug effects / Q000502:physiology*; D010179:Pancreas / Q000648:ultrastructure*; D010306:Parotid Gland / Q000648:ultrastructure*; D051381:Rats
D004792:Enzyme Precursors; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D002118:Calcium