Role of LGI1 in Autosomal Dominant Lateral Temporal Lobe Epilepsy

LGI1 在常染色体显性遗传性外侧颞叶癫痫中的作用

基本信息

批准号：
7777257
负责人：
MATTHEW P ANDERSON
金额：
$ 33.13万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-08-18 至 2012-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7777257
关键词：
2-tyrosine 3-Dimensional ADAM Family Protein Acute Address Adult Afferent Neurons Animals Antibodies Auditory Axon Bacterial Artificial Chromosomes Binding Brain Brain Diseases Cells Complex Computer software Cytoplasmic Granules DLG4 gene DNA Data Dendrites Dependence Development Dimerization Disease Dominant-Negative Mutation Down-Regulation Engineering Epilepsy Figs - dietary Frequencies Gene Expression Genes Genomics Genotype Glioma Glutamate Receptor Glutamates Goals Haploidy Hippocampus (Brain)Human Immunoprecipitation In Vitro Inferior Colliculus Inherited Integrins Ion Channel LGI1 gene Lateral Learning Length Leucine Life Link Long-Term Potentiation Measures Medial Mediating Membrane Methods Modeling Molecular Mus Mutate Mutation N-Methyl-D-Aspartate Receptors N-Methylaspartate NR2B NMDA receptor Neurons PTK2 gene Pathway interactions Pattern Perforant Pathway Physiologic pulse Potassium Channel Probability Process Property Protein Binding Protein Kinase Protein Tyrosine Kinase Protein-Serine-Threonine Kinases Proteins RNA Splicing Receptor Down-Regulation Research Role Sensory Series Signal Pathway Signal Transduction Slice Staining method Stains Structure of molecular layer of cerebellar cortex Synapses Synaptic Transmission Synaptic Vesicles Synaptic plasticity Temporal Lobe Epilepsy Terminator Codon Testing Thalamic structure Time Transcript Transgenic Mice Transgenic Organisms Vesicle Western Blotting base biocytin dendrotoxin density dentate gyrus dimer early childhood entorhinal cortex gamma-Aminobutyric Acid human LGI1 protein in vivo inhibitor/antagonist insight kinase inhibitor mutant nerve supply neural circuit novel patch clamp postnatal postsynaptic premature presynaptic prevent protein complex protein expression public health relevance receptor receptor function reconstruction response src-Family Kinases therapeutic target transmission process

项目摘要

DESCRIPTION (provided by applicant): A recently discovered human epilepsy gene, LGI1 (leucine-rich glioma-inactivated; mutated to cause human autosomal dominant lateral temporal lobe epilepsy or ADLTE) encodes a protein secreted at glutamate synapses during postnatal glutamate synapse development. Consequently, we hypothesize that LGI1 might promote epilepsy through a novel mechanism, by regulating postnatal glutamate synapse maturation. We propose ADLTE mutant LGI1 acts as a dominant negative to inhibit native LGI1 function and arrest maturation. To directly address our hypothesis and contrast the functional effects of epilepsy-associated mutant LGI1 with those of excess wild-type LGI1 on native neural circuits, we created transgenic mice using bacterial artificial chromosomes (BAC) carrying a large 226 kb fragment of mouse genomic DNA encoding the full-length LGI1 gene. The ADLTE 835delC mutation introduced a premature translational stop codon to generate a truncated LGI1 protein. The full-length gene BAC transgenic approach is important to maintain native patterns of gene expression and transcript splicing in order to assess the genes effects on the glutamate synapse development process in vivo. LGI1 is heavily expressed presynaptically at medial entorhinal cortex perforant pathway glutamate synapses innervating dentate granule neurons (MPP- dentate) and also separately in a synapse targeting thalamus. Our overall goal is to define the cellular basis for human ADLT epilepsy. We specifically test whether excess LGI1 magnifies and mutant LGI1 blocks maturation of the following glutamate synapse properties during the postnatal periods when it becomes expressed and throughout adulthood in dentate gyrus and thalamus. We examine: 1) presynaptic glutamate release down-regulation and role of Kv1.1 K+ channel activity; 2) postsynaptic NR2B NMDA receptor current and synaptic plasticity down-regulation, PSD95-Src complex formation, and the role of Src kinase activity; and 3) dendrite branch (e.g., dentate) and axon input (e.g., thalamus) pruning. This murine model of human ADLT epilepsy could link a novel human epilepsy gene to the arrest of glutamate synapse maturation and potentially defining a cellular basis for human seizure disorders beyond ADLTE. PUBLIC HEALTH RELEVANCE: This project seeks to identify the cellular basis of the inherited human epilepsy disorder caused by mutations in LGI1, a secreted synaptic protein. The results should provide new insights into the cellular and molecular basis of human epilepsy, and help identify new potential therapeutic targets to treat this common brain disorder.

描述（由申请人提供）：最近发现的人类癫痫基因LGI1（富含亮氨酸的胶质瘤灭活；突变以引起人类常染色体显性骨呈颞叶癫痫或ADLTE）编码在生成后脑胶质胶状突触过程中分泌在谷氨酸突触的蛋白质的蛋白质。因此，我们假设LGI1可以通过调节产后谷氨酸突触成熟来通过一种新的机制来促进癫痫。我们提出ADLTE突变体LGI1作为抑制天然LGI1功能和停滞成熟的主要负面。为了直接解决我们的假设并将癫痫相关的突变体LGI1与过量野生型LGI1的功能作用，我们使用带有226 KB大型基因组DNA的大型大型基因组DNA的大型基因组碎片的细菌人工染色体（BAC）创建了转基因小鼠。 ADLTE 835DELC突变引入了过早的翻译终止密码子，以生成截短的LGI1蛋白。全长基因BAC转基因方法对于维持基因表达和转录本剪接的天然模式很重要，以评估基因对体内谷氨酸突触发育过程的影响。 LGI1在内侧内侧皮层孔孔孔谷氨酸谷氨酸谷氨酸神经神经神经元（MPP-抑制）上大量表达，并在靶向丘脑的突触中分别分别表示。我们的总体目标是定义人ADLT癫痫的细胞基础。我们明确测试过量的LGI1是否放大和突变体LGI1是否会在产后表达并在整个齿状回和丘脑中表达谷氨酸突触的成熟。我们检查：1）突触前谷氨酸释放下调和KV1.1 K+通道活性的作用； 2）突触后NR2B NMDA受体电流和突触可塑性下调，PSD95-SRC复合物的形成以及SRC激酶活性的作用；和3）树突分支（例如，齿状）和轴突输入（例如丘脑）修剪。人类ADLT癫痫的这种鼠模型可以将一种新型的人类癫痫基因与谷氨酸突触成熟的停滞联系起来，并有可能定义ADLTE以外的人类癫痫发作的细胞基础。公共卫生相关性：该项目旨在确定由分泌的突触蛋白LGI1突变引起的遗传性人癫痫疾病的细胞基础。结果应为人类癫痫的细胞和分子基础提供新的见解，并有助于确定治疗这种常见脑疾病的新潜在治疗靶标。