FORMATION AND ELIMINATION OF SYNAPSES

这项研究的长期目标是阐明细胞 以及发育、维持和可塑性的分子机制 突触 本提案将侧重于参与 细胞外基质（ECM）糖缀合物在这些过程中， 使用花生凝集素（PNA）作为分子的神经肌肉接头（NMJ） 探针 具体目标是： （一）为了验证突触ECM的表达先于突触形成的假设， 突触重塑过程中的神经末梢生长。 (A)已识别的NMJ 将通过视频增强显微镜在体内反复观察 然后进行电子显微镜检查。 此外，无论雪旺细胞 将研究导致神经末梢的过程。 (B)动态 神经末梢、突触ECM和乙酰胆碱之间的关系 将在体内检查发芽活跃生长期间的受体。 （二）.为了表征PNA结合分子（PNA-BM）并测试其 功能协调发展的 (A)亲和层析、凝胶电泳和凝集素 印迹法将用于分离和鉴定PNA-BM。 （B） 将产生针对PNA-BM的抗体，并进行免疫细胞化学和免疫细胞化学。 进行免疫印迹。 (C)亲和纯化的PNA-BM 和功能干扰与抗体对神经突生长在体外 将被审查。 (D)将应用抗体来干扰功能 PNA-BM在突触形成和维持中的作用。 拟议的研究将为ECM的作用提供新的概念 和雪旺氏细胞在突触重塑过程中的作用。 该提案还将描述新的突触特异性ECM分子 并测试其在形成、可塑性和维持中的作用。 NMJ 这一结果可能有助于更好地了解神经肌肉 疾病和创伤后的恢复。 这项研究还可能提供新的 对学习和记忆的思考，这可能涉及突触的重塑， 大脑中的连接。

The long-term objectives of this research are to elucidate the cellular and molecular mechanisms of development, maintenance and plasticity of the synapse. The present proposal will focus on the involvement of extracellular matrix (ECM) glycoconjugates in these processes at the neuromuscular junction (NMJ) using peanut agglutinin (PNA) as a molecular probe. The specific aims are: (I). To test the hypothesis that expression of synaptic ECM precedes the nerve terminal outgrowth during synaptic remodeling. (A) Identified NMJs will be observed repeatedly in vivo with video-enhanced microscopy followed by electron microscopy. In addition, whether Schwann cell processes lead the nerve terminal will be studied. (B) The dynamic relationship among nerve terminals, synaptic ECM and acetylcholine receptors during the active growth of sprouting will be examined in vivo. (II). To characterize PNA-binding molecules (PNA-BMs) and test their functions. (A) Affinity chromatography, gel electrophoresis and lectin blotting will be used to isolate and identify the PNA-BMs. (B) Antibodies against PNA-BMs will be produced and immunocytochemistry and immunoblotting performed. (C) The effects of affinity-purified PNA-BMs and functional perturbation with antibodies on neurite outgrowth in vitro will be examined. (D) Antibodies will be applied to perturb the function of PNA-BMs in synapse formation and maintenance in vitro and in vivo. The proposed research would provide novel concepts on the role of the ECM and Schwann cells during synaptic remodeling in living adult animals. The proposal would also characterize new synapse-specific ECM molecules and test the function in formation, plasticity and maintenance of the NMJ. The result may lead to a better understanding of neuromuscular diseases and restoration after trauma. The study may also provide new thinking on learning and memory, which may involve remodeling of synaptic connections in the brain.