ISSN:
0263-6484
Keywords:
syntaxin
;
epimorphin
;
exocytosis
;
insulinoma
;
insulin release
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
This study was designed in order to examine the expression and functional role of syntaxin 2/epimorphin in pancreatic β cells. Northern blot analysis revealed that syntaxin 2 mRNA was able to be detected in mouse βTC3 cells, but not in isolated mouse islets. In agreement with this result, immunoblot analysis detected an appreciable amount of syntaxin 2 protein in βTC3 cells, but not in mouse islets. Immunohistochemistry of the mouse pancreas demonstrated that syntaxin 2 was little evident in islet cells of Langerhans, and somewhat predominant in exocrine tissues. In order to examine whether syntaxin 2 is anchored to cell surfaces in βTC3 cells, living cells were incubated with a monoclonal antibody against syntaxin 2 (MC-1). The antibody bound to their surfaces, indicating that syntaxin 2 was localized on cell surfaces. The addition of MC-1 to the culture medium of βTC3 cells did not affect insulin release under the presence or absence of 11 mM glucose, indicating that syntaxin 2 is not associated with insulin exocytosis. Thus, the expression of syntaxin 2 in islets of Langerhans is very low and the function of this protein is probably unrelated to the insulin exocytosis pathway. © 1997 John Wiley & Sons, Ltd.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
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