Signal Transduction in Cultured Neural Cells

中枢神经系统内的信号转导涉及 神经递质或神经调质的识别 特异性受体和随后的激活（或抑制） 一个细胞事件。 这些细胞事件（离子易位， 神经递质释放等）通常由第二个 由于受体占据而诱发的信使。 博士 Rasenick将确定如何在 就腺苷酸环化酶而言， 第二信使系统 培养的神经胶质细胞、神经元细胞或杂交细胞 细胞将用皂苷透化， 将原位探测腺苷酸环化酶系统。 博士 Rasenick的实验室开发了一种腺苷酸的测定方法 环化酶（与cAMP积累相反） 细胞; C6 NG.108.15和NCB.20细胞将用于 提出的实验。 最初，Rasenick博士将研究 受体介导的腺苷酸活化的动力学 环化酶系统通过刺激性GTP结合蛋白 （GNs）。将研究激动剂催化的GN活化 用GTP光亲和探针 本研究还将探讨 最近发现的GNs和 抑制性GTP结合蛋白（GNi）通过动力学 实验和光亲和实验。 拉塞尼克博士 证明GTP类似物可以在GN之间交换 和GNi（以及微管蛋白和GNi）; 进一步打算研究受体在 核苷酸交换过程。 透化细胞 为这些实验提供了理想的环境;许多 可协同作用以修饰受体的元件 在这个系统中保留了响应性。 作为皂苷 处理过的细胞具有足够大的孔， 通过蛋白质和Fab片段，各种实验 探索细胞骨架的作用，以及 新发现的32 KDa GTP结合蛋白。 最后，形态分化的影响将是 考察 这项研究提供了令人兴奋的可能性， 研究细胞对神经递质的反应， 类似于完整神经元的环境。

Signal transduction within the central nervous system involves the recognition of a neurotransmitter or neuromodulator by a specific receptor and the subsequent activation (or inhibition) of a cellular event. These cellular events (ion translocation, neurotransmitter release, etc.) are often mediated by second messengers evoked as a result of receptor occupancy. Dr. Rasenick will determine how a number of components within the neuron are integrated with respect to the adenylate cyclase second messenger system. Cultured glial, neuronal or hybrid cells will be permeabilized with saponin, and the components of the adenylate cyclase system will be probed, in situ. Dr. Rasenick's laboratory has developed an assay for adenylate cyclase (as opposed to cAMP accumulation) in permeabilized cells; C6 NG.108.15 and NCB.20 cells will be used for the proposed experiments. Initially, Dr. Rasenick will study the kinetics for the receptor mediated activation of the adenylate cyclase system through the stimulatory GTP binding protein (GNs). The agonist catalyzed activation of GNs will be studied with a GTP.photoaffinity probe. This study also will examine the recently discovered interaction between GNs and the inhibitory GTP binding protein (GNi) both through kinetic experiments and by photoaffinity experiments. Dr. Rasenick has demonstrated that GTP analogues may be exchanged between GNs and GNi (as well as tubulin and GNi) in synaptic membranes; he further intends to examine the possible role of receptors in the nucleotide exchange process. The permeabilized cells provide the ideal milieu for such experiments; many of the elements which may act in concert to modify receptor responsiveness are retained in this system. As the saponin treated cells have holes sufficiently large to allow the passage of proteins and Fab fragments, a variety of experiments to probe the role of the cytoskeleton, as well as that of a newly discovered 32KDa GTP binding protein, are planned. Lastly, effects of morphological differentiation will be examined. This research provides the exciting possibility to investigate the cellular response to neurotransmitters in a environment resembling that of the intact neuron.