RRC ID 49208
Author Imai A, Nashida T, Shimomura H.
Title Roles of Munc18-3 in amylase release from rat parotid acinar cells.
Journal Arch Biochem Biophys
Abstract Several "soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor" (SNARE) proteins have been identified in rat parotid acinar cells, including VAMP-2, syntaxin 4, and SNAP-23. Furthermore, an association between Munc18c (Munc18-3) and syntaxin 4 has been reported. However, the role of Munc18-3 in secretory granule exocytosis on parotid acinar cells remains unclear. In the present study, we investigated the role of Munc18-3 in rat parotid acinar cells. Munc18-3 was localized on the apical plasma membrane where exocytosis occurs and interacted with syntaxin 4. Anti-Munc18-3 antibody dose-dependently decreased isoproterenol (IPR)-induced amylase release from SLO-permeabilized parotid acinar cells. Furthermore, stimulation of the acinar cells with IPR induced translocation of Munc18-3 from the plasma membrane to the cytosol. Munc-18-3 was not phosphorylated by a catalytic subunit of protein kinase (PK) A but phosphorylated by PKC. Treatment of the plasma membrane with PKC but not PKA induced displacement of Munc18-3 from the membrane. The results indicate that Munc18-3 regulates exocytosis in the acinar cells for IPR-induced amylase release and that phosphorylation of Munc18-3 by PKA is not involved in the mechanism.
Volume 422(2)
Pages 175-82
Published 2004-2-15
DOI 10.1016/j.abb.2003.12.021
PII S0003986103006982
PMID 14759605
MeSH Amylases / biosynthesis Amylases / metabolism* Animals Antibodies / pharmacology Bacterial Proteins Base Sequence Cell Membrane / metabolism Cell Membrane Permeability / drug effects Cell Membrane Permeability / physiology Cyclic AMP-Dependent Protein Kinases / metabolism Cytosol / metabolism Isoproterenol / pharmacology Membrane Proteins / metabolism Molecular Sequence Data Munc18 Proteins Nerve Tissue Proteins* Parotid Gland / cytology Parotid Gland / enzymology Parotid Gland / metabolism* Phosphorylation Protein Kinase C / metabolism Proteins / genetics Proteins / immunology Proteins / metabolism* Qa-SNARE Proteins Rats Secretory Vesicles / metabolism Streptolysins / pharmacology Subcellular Fractions / metabolism Vesicular Transport Proteins*
IF 3.559
Times Cited 35
DNA material pEF-FLAG-rat Munc18-2 (RDB15178) pEF-FLAG-rat Munc18-3 (RDB15179).