Nascent SOD1 in Amyotrophic Lateral Sclerosis

肌萎缩侧索硬化症中的新生 SOD1

基本信息

批准号：
8397508
负责人：
Peter JOHN HART
金额：
--
依托单位：
SOUTH TEXAS VETERANS HEALTH CARE SYSTEM
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-10-01 至 2014-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8397508
关键词：
3-Dimensional Address Adopted Affect Affinity Age Aging-Related Process Amino Acid Substitution Amino Acids Amyotrophic Lateral Sclerosis Antioxidants Behavior Binding Binding Sites Biochemistry Cessation of life Child Complex Consultations Copper Cultured Cells DNA Sequence Rearrangement Data Defect Degenerative Disorder Dimensions Disease Dissociation Disulfides Enzymes Event Exercise Failure Familial Amyotrophic Lateral Sclerosis Family Future Gel Chromatography Generations Genes Health Sciences Hospitals Human Inherited Ions Iraq Laboratories Lead Lesion Letters Light Link Measurement Mediating Metalloproteins Metals Methods Military Personnel Modeling Molecular Molecular Chaperones Molecular Conformation Motion Motor Neuron Disease Motor Neurons Mus Mutation Neurodegenerative Disorders Neurons Paralysed Parents Pathway interactions Patients Population Post-Translational Protein Processing Process Proline Proteins Relative (related person)Reporting Resolution SOD1 gene Sampling Site Solutions Spinal Cord Structure Study Section Temperature Testing Texas Therapeutic Therapeutic Agents Time Toxic effect Transgenic Mice Translating United States Universities Variant Veterans War Work X ray diffraction analysis X-Ray Crystallography X-Ray Diffraction analytical ultracentrifugation base cofactor conformer copper zinc superoxide dismutase design disease-causing mutation disulfide bond gain of function gel electrophoresis human tissue in vivo interest melting molecular mass mouse model mutant oxidation polypeptide protein aggregation protein misfolding public health relevance relating to nervous system research study sedimentation equilibrium sedimentation velocity tool

项目摘要

DESCRIPTION (provided by applicant): Mutations in human copper-zinc superoxide dismutase (SOD1) cause an inherited form of the fatal neurodegenerative disease amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease, motor neuron disease). With increasing age, insoluble forms of mutant SOD1 progressively accumulate in neural tissues of human ALS patients and in spinal cords of transgenic mice expressing these polypeptides, suggesting that SOD1- linked ALS is a protein misfolding and aggregation disorder. Understanding the molecular basis for how the pathogenic mutations give rise to SOD1 folding intermediates that are prone to aggregation is therefore of keen interest. A critical step on the folding pathway occurs when the nascent SOD1 polypeptide is posttranslationally modified by the copper chaperone for SOD1 (CCS), a helper protein that inserts the catalytic copper cofactor and oxidizes the SOD1 intrasubunit disulfide bond. CCS recognizes and binds to nascent, but not mature SOD1, suggesting that the newly translated form exists in a conformation distinct from the mature form. Recent studies reveal that pathogenic SOD1 proteins coming from aggregates isolated from cultured cells and from the spinal cords of transgenic mice tend to be metal-deficient and/or lacking the disulfide bond. These observations suggest the hypothesis that the disease-causing mutations may enhance levels of SOD1 folding intermediates by hindering CCS-mediated SOD1 maturation. The experiments outlined in this project are designed to probe the structure and dynamics of nascent SOD1 and to examine its interaction with CCS. Successful completion of the Aims contained herein will address the following questions: 1) What are the structural determinants that are responsible for the recognition of nascent SOD1 by CCS? 2) Is the functional SOD1/CCS complex heterodimeric, heterotetrameric, or some other higher order oligomer? 3) What are the structural details of the nascent SOD1/CCS complex in three dimensions? 4) What factors govern the interconversion of the nascent and mature SOD1 conformations in the absence of CCS? 5) How do the ALS mutations affect the interconversion of the nascent and mature conformations? Answers to these questions are prerequisites for the design of therapeutic agents aimed inhibiting pathogenic SOD1 aggregation in ALS. 1

描述（由申请人提供）：人铜锌超氧化物歧化酶 (SOD1) 的突变会导致遗传性致命的神经退行性疾病肌萎缩侧索硬化症（ALS、卢伽雷氏病、运动神经元病）。随着年龄的增长，不溶性形式的突变体SOD1逐渐在人类ALS患者的神经组织和表达这些多肽的转基因小鼠的脊髓中积累，表明SOD1相关的ALS是一种蛋白质错误折叠和聚集障碍。因此，了解致病性突变如何产生易于聚集的 SOD1 折叠中间体的分子基础引起了人们的浓厚兴趣。当新生的 SOD1 多肽被 SOD1 铜伴侣蛋白 (CCS) 进行翻译后修饰时，折叠途径中的一个关键步骤就会发生。SOD1 铜伴侣蛋白是一种辅助蛋白，插入催化铜辅因子并氧化 SOD1 亚基内二硫键。 CCS 识别并结合新生的 SOD1，但不识别成熟的 SOD1，这表明新翻译的形式以不同于成熟形式的构象存在。最近的研究表明，来自培养细胞和转基因小鼠脊髓中分离的聚集体的致病性 SOD1 蛋白往往缺乏金属和/或缺乏二硫键。这些观察结果表明，致病突变可能通过阻碍 CCS 介导的 SOD1 成熟来提高 SOD1 折叠中间体的水平。该项目中概述的实验旨在探索新生 SOD1 的结构和动力学，并检查其与 CCS 的相互作用。成功完成本文包含的目标将解决以下问题： 1) 导致 CCS 识别新生 SOD1 的结构决定因素是什么？ 2) 功能性 SOD1/CCS 复合物是异二聚体、异四聚体还是其他更高阶的寡聚体？ 3) 新生SOD1/CCS复合体的三维结构细节是什么？ 4) 在没有 CCS 的情况下，哪些因素控制新生和成熟 SOD1 构象的相互转换？ 5）ALS突变如何影响新生构象和成熟构象的相互转换？这些问题的答案是设计旨在抑制 ALS 致病性 SOD1 聚集的治疗药物的先决条件。 1