Friedman Alicia K, Boeynaems Steven, Baker Lane A
Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, 43210, USA.
Department of Genetics, Stanford University School of Medicine, Stanford, CA, 94305, USA.
Anal Bioanal Chem. 2022 Jan;414(1):525-532. doi: 10.1007/s00216-021-03478-2. Epub 2021 Jun 25.
Dipeptide repeats (DPRs) associated with C9orf72 repeat expansions perturb nucleocytoplasmic transport and are implicated in the pathogenesis of amyotrophic lateral sclerosis. We present a synthetic hydrogel platform that can be used to analyze aspects of the molecular interaction of dipeptide repeats and the phenylalanine-glycine (FG) phase of the nuclear pore complex (NPC). Hydrogel scaffolds composed of acrylamide and copolymerized with FG monomers are first formed to recapitulate key FG interactions found in the NPC. With labeled probes, we find evidence that toxic arginine-rich DPRs (poly-GR and poly-PR), but not the non-toxic poly-GP, target NPC hydrogel mimics and block selective entry of a key nuclear transport receptor, importin beta (Impβ). The ease with which these synthetic hydrogel mimics can be adjusted/altered makes them an invaluable tool to dissect complex molecular interactions that underlie cellular transport processes and their perturbation in disease.
与C9orf72重复序列扩增相关的二肽重复序列（DPRs）扰乱核质运输，并与肌萎缩侧索硬化症的发病机制有关。我们展示了一个合成水凝胶平台，可用于分析二肽重复序列与核孔复合体（NPC）的苯丙氨酸-甘氨酸（FG）相之间分子相互作用的各个方面。首先形成由丙烯酰胺组成并与FG单体共聚的水凝胶支架，以重现NPC中发现的关键FG相互作用。使用标记探针，我们发现有证据表明，富含毒性精氨酸的DPRs（聚GR和聚PR），而非无毒的聚GP，靶向NPC水凝胶模拟物并阻断关键核转运受体——输入蛋白β（Impβ）的选择性进入。这些合成水凝胶模拟物易于调整/改变，使其成为剖析细胞运输过程及其在疾病中受到扰动背后复杂分子相互作用的宝贵工具。
