Linked Life Data

8524397

Source:http://linkedlifedata.com/resource/pubmed/id/8524397

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6557
pubmed:dateCreated
1996-1-23
pubmed:abstractText
Rapid and reliable synaptic transmission depends upon the close proximity of voltage-gated calcium channels and neurotransmitter-containing vesicles in the presynaptic terminal. Although it is clear that a local Ca2+ rise conveys the crucial signal from Ca2+ channels to the exocytotic mechanism, little is known about whether communication ever proceeds in the opposite direction, from the release machinery to Ca2+ channels. To look for such signalling, we examined the interaction of various types of voltage-gated Ca2+ channels with syntaxin, a presynaptic membrane protein of relative molecular mass 35,000 which may play a key part in synaptic vesicle docking and fusion and which interacts strongly with N-type Ca2+ channels. Here we report that co-expression of syntaxin 1A with N-type channels in Xenopus oocytes sharply decreases the availability of these channels. This is due to the stabilization of channel inactivation rather than to a simple block or lack of channel expression, because it is overcome by strong hyperpolarization. Deletion of syntaxin's carboxy-terminal transmembrane domain abolishes its functional effect on Ca2+ channels. Syntaxin produced a similar effect on Q-type Ca2+ channels encoded by alpha 1A but not on L-type Ca2+ channels. Thus, the syntaxin effect is specific for Ca2+ channel types that participate in fast transmitter release in the mammalian central nervous system. We hypothesize that, in addition to acting as a vesicle-docking site, syntaxin may influence presynaptic Ca2+ channels, opposing Ca2+ entry where it is not advantageous, but allowing it at release sites where synaptic vesicles have become docked and/or ready for fusion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0028-0836
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
378
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
623-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Functional impact of syntaxin on gating of N-type and Q-type calcium channels.
pubmed:affiliation
Department of Molecular and Cellular Physiology, Stanford University Medical Center, California 94305, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't