Department of Pharmacology, College of Medicine , University of Arizona , Tucson , Arizona 85724 , United States.
Center for Innovation in Brain Science , University of Arizona , Tucson , Arizona 85721 , United States.
ACS Chem Biol. 2019 Sep 20;14(9):2006-2013. doi: 10.1021/acschembio.9b00481. Epub 2019 Aug 27.
RNA dysregulation likely contributes to disease pathogenesis of amyotrophic lateral sclerosis (ALS) and other neurodegenerative diseases. A pathological form of the transactive response (TAR) DNA binding protein (TDP-43) binds to RNA in stress granules and forms membraneless, amyloid-like TDP-43 aggregates in the cytoplasm of ALS motor neurons. In this study, we hypothesized that by targeting the RNA recognition motif (RRM) domains of TDP-43 that confer a pathogenic interaction between TDP-43 and RNA, motor neuron toxicity could be reduced. docking of 50000 compounds to the RRM domains of TDP-43 identified a small molecule (rTRD01) that (i) bound to TDP-43's RRM1 and RRM2 domains, (ii) partially disrupted TDP-43's interaction with the hexanucleotide RNA repeat of the disease-linked gene, but not with (UG) canonical binding sequence of TDP-43, and (iii) improved larval turning, an assay measuring neuromuscular coordination and strength, in an ALS fly model based on the overexpression of mutant TDP-43. Our findings provide an instructive example of a chemical biology approach pivoted to discover small molecules targeting RNA-protein interactions in neurodegenerative diseases.
RNA 失调可能导致肌萎缩侧索硬化症（ALS）和其他神经退行性疾病的发病机制。一种反式激活反应（TAR）DNA 结合蛋白（TDP-43）的病理性形式与应激颗粒中的 RNA 结合，并在 ALS 运动神经元的细胞质中形成无膜、类淀粉样的 TDP-43 聚集物。在这项研究中，我们假设通过靶向 TDP-43 的 RNA 识别基序（RRM）结构域，该结构域赋予 TDP-43 与 RNA 之间的致病相互作用，可以减少运动神经元毒性。将 50000 种化合物对接至 TDP-43 的 RRM 结构域，鉴定出一种小分子（rTRD01），（i）与 TDP-43 的 RRM1 和 RRM2 结构域结合，（ii）部分破坏 TDP-43 与疾病相关基因的六核苷酸 RNA 重复序列的相互作用，但不与 TDP-43 的（UG）经典结合序列结合，以及（iii）改善基于突变 TDP-43 过表达的 ALS 果蝇模型中的幼虫转弯，该测定用于测量神经肌肉协调性和强度。我们的发现为一种化学生物学方法提供了一个有指导意义的范例，该方法旨在发现针对神经退行性疾病中 RNA-蛋白质相互作用的小分子。
