Stabilizing fALS SOD1 Variants by Crosslinking Subunits

描述（由申请人提供）：编码SOD1的基因中有超过120个突变与肌萎缩侧索硬化症相关。SOD1突变导致毒性，一个普遍的假设是，功能获得涉及到SOD1二聚体的解离，然后是聚集。因此，SOD1二聚体的稳定已成为SOD1治疗的一种方法。我们发现了一种特定的化学计量学方法，通过用共价交联剂拴住Cys111残基来稳定SOD1二聚体。Cys111是位于二聚体界面的表面残基，与相对单体上的Cys111（8¿）仅相距很短的距离。我们的假设是，桥接Cys111残基的化合物将作为稳定fALS SOD1变异体的新型药理伴侣，并且基于肽的交联剂适合开发定量结构活性模型，可用于创建第二代改进肽。为了激发人们的兴趣，我们的第一个目标是扩大我们最初发现的范围，包括五种最常见的als变体。虽然我们的第一代交联剂在体外效果良好，但已知它们在体内是有毒的。因此，我们的第二个目标是创建一类新的肽类化学物质，优化以交联Cys111。

DESCRIPTION (provided by applicant): Over 120 mutations in the gene encoding SOD1 are associated with amyotrophic lateral sclerosis. SOD1 mutations result in a toxic property, and a prevailing hypothesis is that a gain-of-function involves dissociation of the SOD1 dimer followed by aggregation. As a result, stabilization of the SOD1 dimer has become an approach for SOD1 therapy. We have discovered a specific and stoichiometric method for stabilizing the SOD1 dimer by tethering Cys111 residues with a covalent cross-linker. Cys111 is a surface residue situated at the dimer interface, and only a short distance apart from the Cys111 (8¿) on an opposing monomer. Our hypothesis is that compounds that bridge Cys111 residues will function as novel pharmacological chaperones that stabilize fALS SOD1 variants and that peptide-based cross-linkers are suitable for developing a quantitative structure activity model that can be used to create a second generation of improved peptides. In the hopes of inspiring interest, our first aim is to expand the scope of our original findings to include the five most prevalent fALS variants. While our first generation cross-linkers work well in vitro, they known to be toxic in vivo. Therefore, our second aim is to create a new class of peptide-based chemicals that are optimized to cross-link Cys111. PUBLIC HEALTH RELEVANCE: The neurodegenerative diseases, including ALS, have proven extraordinarily difficult to treat, for example, ALS has only one FDA-approved drug for its treatment, reporting little or no effect on patient survival and quality of life. Until recently researchers did not understand the mechanism of ALS- associated proteins' toxicity, but now many believe this involves the dissociation of the protein SOD1 from a dimer into two monomers. Preventing this dissociation has become a focus for therapy, and we have discovered a novel and effective in vitro strategy for stabilizing SOD1 that cross-links individual monomers. This proposal aims to expand the scope of our original findings by testing the most prevalent SOD1 variants, and to develop and optimize molecules that are less toxic than our first generation of cross-linkers.