Evidence for the putative docking/fusion complex of exocytosis in parotid acinar cells.
In lysates of the rat brain, the SNARE complex, a putative membrane fusion machinery of synaptic exocytosis, is extremely stable and is detected after SDS-PAGE. Applying this technique to parotid acinar cells, however, we could only detect the monomeric VAMP-2, but not the high molecular forms associated with other components of the SNARE complex. Parotid acini did not contain brain-type t-SNAREs, but contained NSF and alpha SNAP. When VAMP-2 was immunoprecipitated from parotid acinar cell lysates, NSF and alpha SNAP were coprecipitated with it. Since NSF and alpha SNAP are unable to bind directly to VAMP-2 but indirectly bind via t-SNAREs, the immunoprecipitate very likely contained unidentified t-SNAREs.
Takuma
T
T
Department of Oral Biochemistry, School of Dentistry, Health Sciences University of Hokkaido, Japan. takuma@hucc.hokudai.ac.jp
Tagaya
M
M
Ichida
T
T
D000818:Animals; D002474:Cell-Free System / Q000502:physiology; D003594:Cytoplasmic Granules / Q000502:physiology; D005089:Exocytosis; D008561:Membrane Fusion; D008565:Membrane Proteins / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000502:physiology; D010306:Parotid Gland / Q000166:cytology / Q000502:physiology*; D051381:Rats; D050600:SNARE Proteins; D013570:Synaptic Membranes / Q000502:physiology; D033921:Vesicular Transport Proteins
D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins