Abstract
Ca v2.1 and Ca v2.2 channels conduct P/Q-type and N-type Ca 2+ currents that initiate neurotransmission and bind SNARE proteins through a synaptic protein interaction (synprint) site. PKC and CaMKII phosphorylate the synprint site and inhibit SNARE protein binding in vitro. Here we identify two separate microdomains that each bind syntaxin 1A and SNAP-25 in vitro and are regulated by PKC phosphorylation at serines 774 and 898 and CaMKII phosphorylation at serines 784 and 896. Activation of PKC resulted in its recruitment to and phosphorylation of Ca V2.2 channels, but PKC phosphorylation did not dissociate Ca V2.2 channel/syntaxin 1A complexes. Chimeric Ca V2.1a channels containing the synprint site of Ca v2.2 gain modulation by syntaxin 1A, which is blocked by PKC phosphorylation at the sites identified above. Our results support a bipartite model for the synprint site in which each SNARE-binding microdomain is controlled by a separate PKC and CaMKII phosphorylation site that regulates channel modulation by SNARE proteins.
Original language | English |
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Pages (from-to) | 1-17 |
Number of pages | 17 |
Journal | Molecular and Cellular Neuroscience |
Volume | 28 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2005 |
Bibliographical note
Funding Information:We thank Dr. T.P. Snutch (University of British Columbia) for Ca V 2.1 and Ca v 2.2 cDNAs, Dr. M. Wilson (University of New Mexico) for SNAP-25B cDNA, and Dr. Masami Takahashi (Kitasato University) for syntaxin 1A cDNA and Dr. Thomas Soderling (Vollum Institute) for CaMKII. This research was supported by an NRSA from NIH Training Grant T32 NS007332 to S.J.M., NRSA 1F32NS11030 to S.M.M., and NIH Research Grant NS22625 to W.A.C.
Funding
We thank Dr. T.P. Snutch (University of British Columbia) for Ca V 2.1 and Ca v 2.2 cDNAs, Dr. M. Wilson (University of New Mexico) for SNAP-25B cDNA, and Dr. Masami Takahashi (Kitasato University) for syntaxin 1A cDNA and Dr. Thomas Soderling (Vollum Institute) for CaMKII. This research was supported by an NRSA from NIH Training Grant T32 NS007332 to S.J.M., NRSA 1F32NS11030 to S.M.M., and NIH Research Grant NS22625 to W.A.C.
Funders | Funder number |
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National Institutes of Health (NIH) | T32 NS007332, 1F32NS11030 |
National Institute of Neurological Disorders and Stroke | R01NS022625 |
Israel National Road Safety Authority |
ASJC Scopus subject areas
- Molecular Biology
- Cellular and Molecular Neuroscience
- Cell Biology