Interaction of SNARE Complexes with P/Q-type Calcium Channels in Rat Cerebellar Synaptosomes (*)
Interaction of SNARE Complexes with P/Q-type Calcium Channels in Rat Cerebellar Synaptosomes (*)
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SNARE 复合物与大鼠小脑突触体中 P/Q 型钙通道的相互作用 (*)
DOI：
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发表时间：
1996
影响因子：
4.8
通讯作者：
M. Seagar
中科院分区：
文献类型：
--
作者：
N. Martin‐Moutôt;N. Charvin;C. Lévêque;Kazuki Sato;T. Nishiki;S. Kozaki;Masami Takahashi;M. Seagar
P-和Q-型钙通道，触发快速神经递质释放在许多哺乳动物的突触，被阻断芋螺毒素MVIIC。I-芋螺毒素MVIIC与大鼠小脑突触体的结合不被-芋螺毒素GVIA或MVIIA（K > 1 μM）所取代，后者对N-型钙通道具有选择性。溶解的I--芋螺毒素MVIIC受体被针对αA钙通道亚基的抗体特异性识别，α A钙通道亚基是已知构成具有P/Q样通道特性的孔的蛋白质。针对突触融合蛋白1、SNAP 25和VAMP 2（突触泡蛋白）的抗体各自免疫沉淀类似分数（20-40%）的α-芋螺毒素MVIIC受体。免疫沉淀是不加性的，这表明含有这三种蛋白质的异源三聚体（SNARE）复合物与P/Q型钙通道相互作用。固定化的单克隆抗突触融合蛋白抗体保留了220、180和160 kDa的αA钙通道亚基，通过用定点抗体进行免疫印迹来监测。在通道相关复合物中检测到突触结合蛋白，但未检测到突触素、Rab 3A或大鼠半胱氨酸串蛋白。三聚体SNARE复合物参与钙依赖性胞吐，这一过程被认为是由突触结合蛋白调节的。我们的研究结果表明，这些蛋白质与P/Q型钙通道，这可能会优化其在钙内流的域中的位置。
P- and Q-type calcium channels, which trigger rapid neurotransmitter release at many mammalian synapses, are blocked by -conotoxin MVIIC. I--Conotoxin MVIIC binding to rat cerebellar synaptosomes was not displaced by -conotoxins GVIA or MVIIA (K > 1 μM), which are selective for N-type calcium channels. Solubilized I--conotoxin MVIIC receptors were specifically recognized by antibodies directed against αA calcium channel subunits, proteins known to constitute a pore with P/Q-like channel properties. Antibodies against syntaxin 1, SNAP 25, and VAMP 2 (synaptobrevin) each immunoprecipitated a similar fraction (20-40%) of -conotoxin MVIIC receptors. Immunoprecipitation was not additive, suggesting that heterotrimeric (SNARE) complexes containing these three proteins interact with P/Q-type calcium channels. Immobilized monoclonal anti-syntaxin antibodies retained αA calcium channel subunits of 220, 180 and 160 kDa monitored by immunoblotting with site directed antibodies. Synaptotagmin was detected in channel-associated complexes, but not synaptophysin, Rab 3A nor rat cysteine string protein. Trimeric SNARE complexes are implicated in calcium-dependent exocytosis, a process thought to be regulated by synaptotagmin. Our results indicate that these proteins interact with P/Q-type calcium channels, which may optimize their location within domains of calcium influx.
影响因子：
3.4
作者：
LLINAS, R;STEINBERG, IZ;WALTON, K
通讯作者：
WALTON, K
影响因子：
56.9
作者：
WHEELER, DB;RANDALL, A;TSIEN, RW
通讯作者：
TSIEN, RW