REGULATION OF THE CHOLINERGIC COTRANSPORTER--MOLECULAR ASPECTS

高亲和力胆碱转运系统已被表征为支持胆碱能传递的基本要素。该转运蛋白对钠具有强制性需求，并共同转运钠（ChCoT）。这种共转运蛋白的一个重要特征是转运活性似乎可以调节神经元的活性。ACh的调节需要满足，因此在生理上具有高度的重要性。负责ChCoT的这种生理调节的精确分子机制还不清楚。我们提出了一个三部分的假设来解释这种生理调节的ChCoT。我们提出的假设的第一部分是胆碱能突触的胆碱转运率的变化反映了质膜中活性ChCoTs数量的平行变化。该假设的第二部分是，ChCoT的数量是由含有ChCoT的载体囊泡的调节和组成性循环确定的终（质膜），是由含有ChCoT的载体囊泡的调节和组成性循环确定的终（质膜），在细胞溶质和质膜之间的细胞溶质隔室处于细胞内信使的影响下。为了检验这三个部分的假设，我们将完成以下一组具体目标。1. 建立循环ChCoT的囊泡性质，并表征参与此循环的分子机制。2.确定蛋白激酶C（PKC）参与ChCoT囊泡循环的分子机制。3.分离、纯化并开始表征载体囊泡，该载体囊泡作为ChCoT可募集池的细胞质来源。

A high affinity choline transport system has been characterized as an essential element in supporting of cholinergic transmission. This transporter has a obligatory requirement for, and co-transports sodium (ChCoT). An important feature of this co-transporter is that the transport activity appears to adjust neuronal activity. The adjustment of ACh to be met and thus is physiologically highly significant. The precise molecular mechanisms responsible for this physiological regulation of the ChCoT are not well understood. We propose a three part hypothesis to explain this physiological regulation of the ChCoT. The first part of our proposed hypothesis is that the changes in the transport rates of choline at the cholinergic synapse reflect parallel changes in the number of active ChCoTs in the plasma membrane. The second part of the hypothesis is that the number of ChCoTs is the terminal (plasma) membrane in determined by the regulated and constitutive cycling of carrier vesicles containing ChCoTs is the terminal (plasma) membrane in determined by the regulated and constitutive cycling of carrier vesicles containing ChCoTs between a cytosolic compartment between the cytosol and the plasma membrane is under the influence of intracellular messengers. To test this three part hypothesis we will accomplish the following set of Specific Aims. 1. Establish the vesicular nature of the cycling ChCoT and characterize the molecular mechanisms involved in this cycling. 2. Determine the molecular mechanism of protein kinase C (PKC) involvement in the cycling of ChCoT vesicles. 3. Isolate,, purify and initiate the characterization of the carrier vesicle that serves as the cytoplasmic source of the recruitable pool of ChCoTs.