TY - JOUR
T1 - Identification of synaptic proteins and their isoform mRNAs in compartments of pancreatic endocrine cells
AU - Jacobsson, Gunilla
AU - Bean, Andrew J.
AU - Scheller, Richard H.
AU - Juntti-Berggren, Lisa
AU - Deeney, Jude T.
AU - Berggren, Per Olof
AU - Meister, Björn
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 1994/12/20
Y1 - 1994/12/20
N2 - Several proteins that are of importance for membrane trafficking in the nerve terminal have recently been characterized. We have used Western blot and immunohistochemistry to show that synaptotagmin, synaptobrevin/VAMP (vesicle-associated membrane protein), SNAP-25 (synaptosomal-associated protein of 25 kDa), and syntaxin proteins are present in cells of the islets of Langerhans in the endocrine pancreas. Synaptotagmin-like immunoreactivity (-LI) was localized to granules within the cytoplasm of a few endocrine cells located in the periphery of the islets, identified as somatostatin-containing cells, and in many nerve fibers within the islets. VAMP-LI was seen in granules of virtually all pancreatic islet cells and also in nerve fibers. SNAP-25-LI and syntaxin-LI were predominantly present in the plasma membrane of the endocrine cells, including insulin-producing β cells. In situ hybridization, using isoform-specific oligonucleotide probes, detected VAMP- 2, cellubrevin, SNAP-25, syntaxin 1A, 4, and 5, and munc-18 mRNAs in isolated pancreatic islets and in insulin-producing cells. The results show the presence of several synaptic proteins at protein and mRNA levels in pancreatic islet cells, suggesting that they may have specific roles in the molecular regulation of exocytosis also in insulin-secreting cells.
AB - Several proteins that are of importance for membrane trafficking in the nerve terminal have recently been characterized. We have used Western blot and immunohistochemistry to show that synaptotagmin, synaptobrevin/VAMP (vesicle-associated membrane protein), SNAP-25 (synaptosomal-associated protein of 25 kDa), and syntaxin proteins are present in cells of the islets of Langerhans in the endocrine pancreas. Synaptotagmin-like immunoreactivity (-LI) was localized to granules within the cytoplasm of a few endocrine cells located in the periphery of the islets, identified as somatostatin-containing cells, and in many nerve fibers within the islets. VAMP-LI was seen in granules of virtually all pancreatic islet cells and also in nerve fibers. SNAP-25-LI and syntaxin-LI were predominantly present in the plasma membrane of the endocrine cells, including insulin-producing β cells. In situ hybridization, using isoform-specific oligonucleotide probes, detected VAMP- 2, cellubrevin, SNAP-25, syntaxin 1A, 4, and 5, and munc-18 mRNAs in isolated pancreatic islets and in insulin-producing cells. The results show the presence of several synaptic proteins at protein and mRNA levels in pancreatic islet cells, suggesting that they may have specific roles in the molecular regulation of exocytosis also in insulin-secreting cells.
KW - diabetes
KW - exocytosis
KW - insulin
KW - secretion
UR - http://www.scopus.com/inward/record.url?scp=0028580733&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028580733&partnerID=8YFLogxK
U2 - 10.1073/pnas.91.26.12487
DO - 10.1073/pnas.91.26.12487
M3 - Article
C2 - 7809063
AN - SCOPUS:0028580733
VL - 91
SP - 12487
EP - 12491
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 26
ER -