Neuropathy-associated histidyl-tRNA synthetase variants attenuate protein synthesis in vitro and disrupt axon outgrowth in developing zebrafish.
Neuropathy-associated histidyl-tRNA synthetase variants attenuate protein synthesis in vitro and disrupt axon outgrowth in developing zebrafish.
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DOI：
10.1111/febs.15449
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发表时间：
2021-01
期刊：
影响因子：
--
通讯作者：
Francklyn CS
中科院分区：
文献类型：
--
作者：
Mullen P;Abbott JA;Wellman T;Aktar M;Fjeld C;Demeler B;Ebert AM;Francklyn CS
Charcot-Marie-Tooth病(CMT)包括一组遗传和临床上不同的神经病，其特征是周围神经系统的长度依赖性功能障碍。80多个不同基因的突变与CMT有关，氨基酰-tRNA合成酶(ARS)构成了一个与CMT有关的大基因家族。尽管人们努力阐明ARS突变和CMT表型之间的机制联系，但其病理的分子基础尚不清楚。在这项工作中，我们研究了细胞质组氨酰-tRNA合成酶(HARS1)中与CMT相关的三个替换(V155G，Y330C，R137Q)对轴突生长和周围神经系统发育的影响。这项工作的模型系统包括神经生长因子刺激的大鼠嗜铬细胞瘤细胞(PC12)的轴突生长模型，以及带有GFP/RFP记者的斑马鱼系感觉神经元和运动神经元的发育。在两种模型中，CMT-HARS1突变的表达导致PC12细胞蛋白质合成减弱和eIF2α磷酸化增加，并伴有轴突和轴突生长受损。值得注意的是，这些效应被组氨酰-tRNA合成酶抑制剂组氨醇和蛋白质合成抑制剂放线菌亚胺所抑制。突变蛋白还与野生型HARS1形成异二聚体，增加了CMT-HARS1突变通过显性负机制致病的可能性。总体而言，这些发现支持CMT-HARS1等位基因在神经元环境中发挥毒性作用，并导致蛋白质合成失调的假设。这些研究证明了斑马鱼作为研究与CMT相关的突变等位基因以及描述导致周围神经系统功能障碍的过程的模型的价值。周围神经病相关组氨酰-tRNA合成酶(HARS)变异体与野生型HARS形成异源二聚体，破坏周围神经系统的结构和功能。突起生长的缺陷与蛋白质合成的减弱和eIF2α的磷酸化有关。突变的HARS的细胞效应是通过抑制HARS的活性(组氨醇)或蛋白质合成(放线菌酮)来表现出来的。这些结果表明，HARS抑制和蛋白质合成失调可能是周围神经病的关键致病过程。
Charcot-Marie-Tooth disease (CMT) encompasses a set of genetically and clinically heterogeneous neuropathies characterized by length dependent dysfunction of the peripheral nervous system. Mutations in over 80 diverse genes are associated with CMT, and aminoacyl-tRNA synthetases (ARS) constitute a large gene family implicated in the disease. Despite considerable efforts to elucidate the mechanistic link between ARS mutations and the CMT phenotype, the molecular basis of the pathology is unknown. In this work, we investigated the impact of three CMT-associated substitutions (V155G, Y330C, R137Q) in the cytoplasmic histidyl-tRNA synthetase (HARS1) on neurite outgrowth and peripheral nervous system development. The model systems for this work included a nerve growth factor stimulated neurite outgrowth model in rat pheochromocytoma cells (PC12), and a zebrafish line with GFP/RFP reporters of sensory and motor neuron development. Expression of CMT-HARS1 mutations led to attenuation of protein synthesis and increased phosphorylation of eIF2α in PC12 cells and was accompanied by impaired neurite and axon outgrowth in both models. Notably, these effects were phenocopied by histidinol, a histidyl-tRNA synthetase inhibitor, and cycloheximide, a protein synthesis inhibitor. The mutant proteins also formed heterodimers with wild-type HARS1, raising the possibility that CMT-HARS1 mutations cause disease through a dominant negative mechanism. Overall, these findings support the hypothesis that CMT-HARS1 alleles exert their toxic effect in a neuronal context, and lead to dysregulated protein synthesis. These studies demonstrate the value of zebrafish as a model for studying mutant alleles associated with CMT, and for characterizing the processes that lead to peripheral nervous system dysfunction. Peripheral neuropathy associated histidyl-tRNA synthetase (HARS) variants form heterodimers with wild-type HARS and disrupt peripheral nervous system structure and function. Defects in neurite outgrowth are linked to attenuation of protein synthesis and induction of eIF2α phosphorylation. The cellular effects of mutant HARS were phenocopied by inhibition of HARS activity (histidinol) or protein synthesis (cycloheximide). These results suggest that HARS inhibition and dysregulated protein synthesis may be key pathogenic processes in peripheral neuropathy.
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影响因子：
3.5
作者：
Boczonadi V;Jennings MJ;Horvath R
通讯作者：
Horvath R
DOI：
10.1093/brain/awx375
发表时间：
2018-03-01
期刊：
Brain : a journal of neurology
影响因子：
--
作者：
Benoy V;Van Helleputte L;Prior R;d'Ydewalle C;Haeck W;Geens N;Scheveneels W;Schevenels B;Cader MZ;Talbot K;Kozikowski AP;Vanden Berghe P;Van Damme P;Robberecht W;Van Den Bosch L
通讯作者：
Van Den Bosch L
影响因子：
2.4
作者：
Demeler, Borries;Brookes, Emre
通讯作者：
Brookes, Emre
影响因子：
12.7
作者：
Cogli, Laura;Progida, Cinzia;Bucci, Cecilia
通讯作者：
Bucci, Cecilia
影响因子：
5.3
作者：
Antonellis, Anthony;Lee-Lin, Shih-Queen;Green, Eric D.
通讯作者：
Green, Eric D.