Cysteine string proteins: a potential link between synaptic vesicles and presynaptic Ca2+ channels.
Presynaptic calcium channels are key regulators of neurotransmitter release. Oocyte expression studies suggest that cysteine string proteins are essential subunits or modulators of these channels. Subcellular fractionation revealed that cysteine string proteins copurify with synaptic vesicles. An average vesicle had eight protein monomers with both the amino and carboxyl termini detected on the cytoplasmic face. Thus, docked synaptic vesicles may regulate presynaptic calcium channels and neurotransmitter release.
Mastrogiacomo
A
A
Department of Molecular and Medical Pharmacology, UCLA School of Medicine 90024.
Parsons
S M
SM
Zampighi
G A
GA
Jenden
D J
DJ
Umbach
J A
JA
Gundersen
C B
CB
D000818:Animals; D015220:Calcium Channels / Q000378:metabolism*; D002458:Cell Fractionation; D004557:Electric Organ; D008565:Membrane Proteins / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D008854:Microscopy, Electron; D009068:Movement; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D018377:Neurotransmitter Agents / Q000378:metabolism; D017729:Presynaptic Terminals / Q000378:metabolism* / Q000648:ultrastructure; D009435:Synaptic Transmission; D013572:Synaptic Vesicles / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D014101:Torpedo
D015220:Calcium Channels; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents