Calcium-triggered membrane fusion proceeds independently of specific presynaptic proteins

Joseph A Szule; Scott E Jarvis; Dr Julie E Hibbert; J David Spafford; Janice E A Braun; Gerald W Zamponi; Gary M Wessel; Jens R Coorssen

doi:10.1074/jbc.C300197200

Back

Calcium-triggered membrane fusion proceeds independently of specific presynaptic proteins

Journal article

Open access

Peer reviewed

Calcium-triggered membrane fusion proceeds independently of specific presynaptic proteins

Joseph A Szule, Scott E Jarvis, Dr Julie E Hibbert, J David Spafford, Janice E A Braun, Gerald W Zamponi, Gary M Wessel and Jens R Coorssen

The Journal of biological chemistry, Vol.278(27), pp.24251-24254

2003

DOI: https://doi.org/10.1074/jbc.C300197200

PMID: 12764142

Files and links (1)

pdf

Published362.04 kBDownload View

CC BY V4.0, Open Access

Abstract

Animals

Calcium - physiology

Calcium-Binding Proteins

Exocytosis - physiology

Female

Membrane Fusion - physiology

Membrane Glycoproteins - physiology

Membrane Proteins - physiology

Nerve Tissue Proteins - physiology

Protein Binding

Sea Urchins

SNARE Proteins

Synaptotagmins

Vesicular Transport Proteins

Complexes of specific presynaptic proteins have been hypothesized to drive or catalyze the membrane fusion steps of exocytosis. Here we use a stage-specific preparation to test the roles of SNAREs, synaptotagmin, and SNARE-binding proteins in the mechanism of Ca2+-triggered membrane fusion. Excess exogenous proteins, sufficient to block SNARE interactions, did not inhibit either the Ca2+ sensitivity, extent, or kinetics of fusion. In contrast, despite a limited effect on SNARE and synaptotagmin densities, treatments with high doses of chymotrypsin markedly inhibited fusion. Conversely, low doses of chymotrypsin had no effect on the Ca2+ sensitivity or extent of fusion but did alter the kinetic profile, indicating a more direct involvement of other proteins in the triggered fusion pathway. SNAREs, synaptotagmin, and their immediate binding partners are critical to exocytosis at a stage other than membrane fusion, although they may still influence the triggered steps.

Details

Title: Calcium-triggered membrane fusion proceeds independently of specific presynaptic proteins
Authors/Creators: Joseph A Szule - Department of Physiology and Biophysics, Cellular and Molecular Neurobiology Research Group, University of Calgary, Health Sciences Centre, Faculty of Medicine, Alberta T2N 4N1, Canada
Scott E Jarvis
Dr Julie E Hibbert
J David Spafford
Janice E A Braun
Gerald W Zamponi
Gary M Wessel
Jens R Coorssen
Publication Details: The Journal of biological chemistry, Vol.278(27), pp.24251-24254
Publisher: Currently published by Elsevier Inc; originally published by American Society for Biochemistry and Molecular Biology.
Identifiers: 991005636469607891
Murdoch Affiliation: Centre for Molecular Medicine and Innovative Therapeutics; School of Medical, Molecular and Forensic Sciences
Language: English
Resource Type: Journal article

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

Source: InCites

Metrics

35 Record Views

43 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Collaboration types: Domestic collaboration; International collaboration
Citation topics: 1 Clinical & Life Sciences; 1.96 Cell Biology; 1.96.302 Membrane Trafficking
Web Of Science research areas: Biochemistry & Molecular Biology
ESI research areas: Biology & Biochemistry