STUDY ON NEURODEGENERATION USING TDP-43 TRANSGENIC RATS

TDP-43 转基因大鼠神经退行性研究

基本信息

批准号：
10198111
负责人：
hongxia zhou
金额：
$ 31.48万
依托单位：
FLORIDA INTERNATIONAL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-19 至 2021-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10198111
关键词：
3&apos Untranslated Regions ALS patients Affect Affinity Alleles Amyotrophic Lateral Sclerosis Animal Model Binding Binding Proteins Biological Assay Biological Markers Biological Models Complementary DNA DNA Sequence DNA Sequence Alteration Detection Disease Disease Progression Engineering Genes Genetic Heterozygote Human Knock-in Knock-out Link Measures Messenger RNA Modeling Modification Monitor Mus Mutate Mutation Nerve Degeneration Neuraxis Pathogenesis Pathogenicity Pathway interactions Patients Pattern Phenocopy Phenotype Physiological Point Mutation Positioning Attribute Post-Translational Protein Processing Proteins RNA Rattus Rodent Transgenes Transgenic Model Transgenic Organisms Treatment outcome disease phenotype in vivo insight interest knock-down knockin animal loss of function mutant neurotoxic neurotoxicity novel overexpression preservation promoter protein TDP-43 public health relevance rat genome transgene expression

项目摘要

DESCRIPTION (provided by applicant): Among known ALS genes, TDP-43 is of particular interest because its protein is hyper-phosphorylated and ubiquitinated in sporadic ALS. Compared with genetic mutation, post-translational modification is difficult to detect in patients and hard to reproduce in animal models. Therefore, a critical step toward understanding TDP-43 pathogenesis is revealing the pathways by which mutant TDP-43 causes neurodegeneration in ALS. TDP-43 binds to many RNAs and proteins, but how pathogenic mutation impacts TDP-43 function has not yet been determined, particularly in an appropriate animal model. Unexpectedly, overexpression of both WT and mutant TDP-43 in rodents causes indistinguishable phenotypes, indicating that excessive TDP-43 is neurotoxic. Because transgene expression is heavily influenced by position effect, the patterns and levels of transgene expression vary greatly from line to line. Whether mutant TDP-43 is more or less toxic than its WT form thus cannot be determined using existing transgenic models. The question regarding the impact of pathogenic mutation on TDP-43 function is further confounded by observations that TDP-43 depletion induces neurodegeneration in TDP-43 knock-out and knock-down mice. As TDP-43 binds to the 3'-untranslated region of its own mRNA and thereby regulates its own expression, the cDNA knock-in (KI) approach destroys TDP-43 self-regulatory machinery, rendering TDP-43 KI animals not very useful. Even 7 years after the discovery of TDP-43 mutation in ALS, whether mutant TDP-43 causes ALS through a gain or loss of function is still uncertain, and this unresolved issue is a roadblock to unraveling TDP-43 disease mechanisms. To resolve this critical issue, we created KI rats by introducing a single disease-linked point mutation into the rat genome. With the unprecedented rat models, we will determine how pathogenic mutation impacts TDP-43 function in a systematic manner.

描述（由适用提供）：在已知的ALS基因中，TDP-43特别感兴趣，因为其蛋白质被过度磷酸化并在零星的ALS中泛素化。与遗传突变相比，在动物模型中很难检测到翻译后修饰，并且很难繁殖。因此，了解TDP-43发病机理的关键步骤是揭示了突变体TDP-43在ALS中引起神经变性的途径。 TDP-43与许多RNA和蛋白质结合，但是尚未确定致病性突变如何影响TDP-43功能，尤其是在适当的动物模型中。出乎意料的是，啮齿动物中WT和突变体TDP-43的过表达导致无法区分的表型，这表明超级TDP-43是神经毒性的。由于转化表达受位置效应的严重影响，因此转化表达的模式和水平因线而异。因此，无法使用现有的转基因模型确定WT形式。关于致病突变对TDP-43功能的影响的问题进一步混淆，即TDP-43耗竭会诱导TDP-43敲除和敲除小鼠中的神经变性。随着TDP-43与其自己的mRNA的3'-非翻译区域结合，从而调节其自身的表达，cDNA敲入（KI）方法破坏了TDP-43自调节机制，使TDP-43 KI动物渲染不太有用。即使在ALS中发现TDP-43突变的7年后，突变体TDP-43是否通过功能的增长或丧失引起ALS仍然不确定，并且这个尚未解决的问题是揭示TDP-43疾病机制的障碍。为了解决这个关键问题，我们通过将单个疾病连接点突变引入大鼠基因组中创建了Ki大鼠。使用前所未有的大鼠模型，我们将确定致病性突变如何以系统的方式影响TDP-43功能。