Isolation and Characterization of Synaptogenic Proteins

突触蛋白的分离和表征

• 批准号: 7796983
• 负责人: JUAN L BRUSES
• 金额: $ 21.25万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-01 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7796983
• 关键词: Acetylcholine; Affect; Autistic Disorder; Binding; Biological Assay; Cell Adhesion Molecules; Cell Communication; Cell Membrane Proteins; Cell Surface Proteins; Cell membrane; Cell surface; Cells; Coculture Techniques; Collagen; Communication; Coupling; Development; Developmental Disabilities; Developmental Process; Elements; Embryonic Development; Endocytosis; Event; Extracellular Matrix; Extracellular Matrix Proteins; Extracellular Protein; Family; Fibroblast Growth Factor; Foxes; Future; Gene Expression; Gene Proteins; Genes; Goals; Immunoglobulins; In Vitro; Inositol; Laminin; Lead; Leucine-Rich Repeat; Ligands; Link; Membrane; Molecular; Muscle; Nerve; Nervous System Physiology; Neurons; Neurotransmitter Receptor; Nicotinic Receptors; Phase; Polystyrenes; Presynaptic Terminals; Proteins; Psyche structure; Research Project Grants; Schizophrenia; Site; Structure of ciliary ganglion; Surface; Synapses; Synaptic Membranes; Testing; Therapeutic; Therapeutic Intervention; Transcript; combinatorial; genome wide association study; genome-wide; genome-wide analysis; in vivo; membrane activity; nervous system disorder; postsynaptic; presynaptic; programs; protein expression; public health relevance; single molecule; synaptogenesis

DESCRIPTION (provided by applicant): The long-term goal of this research project is to elucidate the molecular mechanisms that regulate the formation of synaptic contacts. Synapses are a central component in the formation and the functioning of the nervous system and become affected in a variety of mental and neurological disorders. Therefore the discovery of the molecules and mechanisms that participate in the establishment of synaptic connections will contribute to our understanding of the formation of neuronal circuits, the causes of mental and neurological disorders, and may identify potential targets for therapeutic interventions. Synapse formation is a well-programmed developmental process that involves a variety of cell-cell interactions carried out by distinct groups of molecules, which are required for the recognition of a postsynaptic target, the stabilization of the contact between synaptic membranes, and the functional coupling between synaptic compartments. The present proposal focuses on the identification and characterization of proteins capable of inducing the formation of synaptic contacts between neurons during embryogenesis. Our central hypothesis is that the expression of membrane tethered or secreted ligands by the presumptive postsynaptic neuron are required to induce the differentiation of the presynaptic terminal and the establishment of a synaptic contact. For this reason, we carried out a genome-wide search for gene-transcripts that become expressed in postsynaptic neurons during the different phases of synapse development. This analysis led to the identification of a group of proteins containing immunoglobulin (Ig) domains, leucine-rich repeats (LRR), or other protein interacting domains that are substantially up-regulated during the initiation phase of synapse formation, and which have the molecular features of cell surface ligands suggesting that these proteins may possess synaptogenic activity. In this two-year project we propose 1) to test experimentally the synaptogenic activity of this subset of proteins up-regulated during the initiation of synapse formation, 2) to examine whether their combinatorial expression is needed to trigger synapse formation, and 3) to test whether cell surface expression of GPI- linked cell adhesion molecules regulates the surface expression levels of nicotinic acetylcholine neurotransmitter receptors. To this aim, in vitro cell assays will be used to determine the synaptogenic activity of these proteins by evaluating presynaptic terminal differentiation and cell surface protein expression levels. The identification of proteins which are sufficient to induce synapse formation in vitro will be further studied in the future to determine whether these proteins are necessary for the initiation of synapse formation in vivo and to examine the molecular mechanisms involved. PUBLIC HEALTH RELEVANCE: The long-term goal of this project is to elucidate the cellular and molecular mechanisms that participate in the assembly of synaptic contacts. The present proposal focuses on the identification and characterization of genes and proteins that participate in the initiation phase of synapse formation. The central hypothesis is that proteins expressed on the surface of presumptive postsynaptic neuron are necessary for inducing the differentiation of a presynaptic terminal at the site of contact. The importance of understanding the molecular mechanisms of synapse formation is underscored by the fact that synapses are the center piece for neuronal communication and become affected in a variety of mental and neurological disorders including, intellectual developmental disabilities, autism, and schizophrenia. Thus, the studies proposed in this application will lead to a better understanding of the molecular mechanisms that participate in the formation of synaptic connections, to the elucidation of the causes of mental and neurological disorders, and to the identification of therapeutic strategies.

描述(申请人提供)：本研究项目的长期目标是阐明调节突触接触形成的分子机制。突触是神经系统形成和功能的中心组成部分，并在各种精神和神经障碍中受到影响。因此，参与建立突触连接的分子和机制的发现将有助于我们理解神经元回路的形成，精神和神经疾病的原因，并可能确定潜在的治疗干预靶点。突触的形成是一个程序化的发育过程，它涉及不同分子群进行的各种细胞-细胞相互作用，这些分子是识别突触后靶点、稳定突触膜之间的接触以及突触间隔之间的功能耦合所必需的。目前的建议集中在鉴定和鉴定能够在胚胎发育过程中诱导神经元之间形成突触接触的蛋白质。我们的中心假设是，假定突触后神经元表达膜系留或分泌的配体是诱导突触前终末分化和建立突触联系所必需的。为此，我们进行了全基因组搜索，寻找在突触发育的不同阶段在突触后神经元表达的基因转录本。这一分析导致了一组含有免疫球蛋白(Ig)结构域、富含亮氨酸重复序列(LRR)或其他蛋白相互作用结构域的蛋白质的鉴定，这些结构域在突触形成的起始阶段大量上调，并具有细胞表面配体的分子特征，表明这些蛋白质可能具有突触生成活性。在这个为期两年的项目中，我们建议1)从实验上测试在突触形成过程中上调的这一蛋白质子集的突触生成活性，2)检查它们的组合表达是否需要触发突触形成，以及3)测试GPI连接的细胞黏附分子的细胞表面表达是否调节烟碱型乙酰胆碱神经递质受体的表面表达水平。为此，体外细胞分析将通过评估突触前终末分化和细胞表面蛋白表达水平来确定这些蛋白的突触生成活性。对于在体外足以诱导突触形成的蛋白质的鉴定将在未来进一步研究，以确定这些蛋白质是否在体内启动突触形成所必需的，并研究其中涉及的分子机制。公共卫生相关性：该项目的长期目标是阐明参与突触接触组装的细胞和分子机制。本提案的重点是识别和表征参与突触形成起始阶段的基因和蛋白质。中心假设是，在假定的突触后神经元表面表达的蛋白质是诱导接触部位的突触前终末分化所必需的。突触是神经元交流的中心，在包括智力发育障碍、自闭症和精神分裂症在内的各种精神和神经疾病中都会受到影响，这一事实突显了了解突触形成的分子机制的重要性。因此，本申请中提出的研究将有助于更好地了解参与突触连接形成的分子机制，阐明精神和神经疾病的原因，并确定治疗策略。