Abstract
To examine the freeze-fracture appearance of membrane alterations at sites of exocytosis in mammalian cells, we studied the secretory granule and plasma membrane of rat pancreatic B-cells during glucose- stimulated insulin secretion. Constant features observed were the scarcity of particles in secretory-granule P-fracture faces and the almost total clearance of intramembranous particles in P-and E fracture faces of the plasma membrane in areas of close apposition of these two membranes preceding fusion; also observed was the temporary persistence of particle-cleared regions after the fusion was completed. Our observations thus support the concept that membranes fuse at sites of closely apposed, particle-free regions and that the physiologically created clear areas found in freeze-fracture replicas of the plasma membrane are the hallmarks of incipient or recent membrane fusion.
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Selected References
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- Chi E. Y., Lagunoff D., Koehler J. K. Freeze-fracture study of mast cell secretion. Proc Natl Acad Sci U S A. 1976 Aug;73(8):2823–2827. doi: 10.1073/pnas.73.8.2823. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dreifuss J. J., Akert K., Sandri C. Specific arrangements of membrane particles at sites of exo-endocytosis in the freeze-etched neurohypophysis. Cell Tissue Res. 1976 Jan 27;165(3):317–325. doi: 10.1007/BF00222436. [DOI] [PubMed] [Google Scholar]
- Lacy P. E. Beta cell secretion--from the standpoint of a pathobiologist. Diabetes. 1970 Dec;19(12):895–905. doi: 10.2337/diab.19.12.895. [DOI] [PubMed] [Google Scholar]
- Lacy P. E., Kostianovsky M. Method for the isolation of intact islets of Langerhans from the rat pancreas. Diabetes. 1967 Jan;16(1):35–39. doi: 10.2337/diab.16.1.35. [DOI] [PubMed] [Google Scholar]
- Lagunoff D. Membrane fusion during mast cell secretion. J Cell Biol. 1973 Apr;57(1):252–259. doi: 10.1083/jcb.57.1.252. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lawson D., Raff M. C., Gomperts B., Fewtrell C., Gilula N. B. Molecular events during membrane fusion. A study of exocytosis in rat peritoneal mast cells. J Cell Biol. 1977 Feb;72(2):242–259. doi: 10.1083/jcb.72.2.242. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lucy J. A. The fusion of biological membranes. Nature. 1970 Aug 22;227(5260):815–817. doi: 10.1038/227815a0. [DOI] [PubMed] [Google Scholar]
- Orci L. A portrait of the pancreatic B-cell. The Minkowski Award Lecture delivered on July 19, 1973, during the 8th Congress of the International Diabetes Federation, held in Brussels, Belgium. Diabetologia. 1974 Jun;10(3):163–187. doi: 10.1007/BF00423031. [DOI] [PubMed] [Google Scholar]
- Orci L., Amherdt M., Malaisse-Lagae F., Perrelet A., Dulin W. E., Gerritsen G. C., Malassie W. J., Renold A. E. Morphological characterization of membrane systems in A- and B-cells of the Chinese hamster. Diabetologia. 1974 Nov;10 (Suppl):529–539. doi: 10.1007/BF01221983. [DOI] [PubMed] [Google Scholar]
- Orci L., Amherdt M., Malaisse-Lagae F., Rouiller C., Renold A. E. Insulin release by emiocytosis: demonstration with freeze-etching technique. Science. 1973 Jan 5;179(4068):82–84. doi: 10.1126/science.179.4068.82. [DOI] [PubMed] [Google Scholar]
- Orci L., Perrelet A. Membrane-associated particles: increase at sites of pinocytosis demonstrated by freeze-etching. Science. 1973 Aug 31;181(4102):868–869. doi: 10.1126/science.181.4102.868. [DOI] [PubMed] [Google Scholar]
- Satir B., Schooley C., Satir P. Membrane fusion in a model system. Mucocyst secretion in Tetrahymena. J Cell Biol. 1973 Jan;56(1):153–176. doi: 10.1083/jcb.56.1.153. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith U., Ryan J. W., Smith D. S. Freeze-etch studies of the plasma membrane of pulmonary endothelial cells. J Cell Biol. 1973 Feb;56(2):492–499. doi: 10.1083/jcb.56.2.492. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stoeckart R., Jansen H. G., Kreike A. J. Ultrastructural evidence for exocytosis in the median eminence of the rat. Z Zellforsch Mikrosk Anat. 1972;131(1):99–107. doi: 10.1007/BF00307203. [DOI] [PubMed] [Google Scholar]
- Tandler B., Poulsen J. H. Fusion of the envelope of mucous droplets with the luminal plasma membrane in acinar cells of the cat submandibular gland. J Cell Biol. 1976 Mar;68(3):775–781. doi: 10.1083/jcb.68.3.775. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yu J., Branton D. Reconstitution of intramembrane particles in recombinants of erythrocyte protein band 3 and lipid: effects of spectrin-actin association. Proc Natl Acad Sci U S A. 1976 Nov;73(11):3891–3895. doi: 10.1073/pnas.73.11.3891. [DOI] [PMC free article] [PubMed] [Google Scholar]