PUBLICATION
Neuropathy-associated histidyl-tRNA synthetase variants attenuate protein synthesis in vitro and disrupt axon outgrowth in developing zebrafish
- Authors
- Mullen, P., Abbott, J.A., Wellman, T., Aktar, M., Fjeld, C., Demeler, B., Ebert, A.M., Francklyn, C.S.
- ID
- ZDB-PUB-200617-18
- Date
- 2020
- Source
- The FEBS journal 288(1): 142-159 (Journal)
- Registered Authors
- Keywords
- Charcot-Marie-Tooth disease, aminoacyl-tRNA synthetase, peripheral neuropathy, protein synthesis, tRNA
- MeSH Terms
-
- Animals
- Animals, Genetically Modified
- Charcot-Marie-Tooth Disease/genetics*
- Charcot-Marie-Tooth Disease/metabolism
- Charcot-Marie-Tooth Disease/pathology
- Cycloheximide/pharmacology
- Disease Models, Animal
- Eukaryotic Initiation Factor-2/genetics
- Eukaryotic Initiation Factor-2/metabolism
- Gene Expression Regulation
- Genes, Reporter
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Histidine-tRNA Ligase/antagonists & inhibitors
- Histidine-tRNA Ligase/genetics*
- Histidine-tRNA Ligase/metabolism
- Histidinol/pharmacology
- Humans
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Mutation
- Neuronal Outgrowth/drug effects
- Neuronal Outgrowth/genetics*
- Neurons/drug effects
- Neurons/metabolism*
- Neurons/pathology
- PC12 Cells
- Peripheral Nervous System/metabolism*
- Peripheral Nervous System/pathology
- Protein Biosynthesis*
- Protein Multimerization
- Rats
- Zebrafish
- PubMed
- 32543048 Full text @ FEBS J.
Citation
Mullen, P., Abbott, J.A., Wellman, T., Aktar, M., Fjeld, C., Demeler, B., Ebert, A.M., Francklyn, C.S. (2020) Neuropathy-associated histidyl-tRNA synthetase variants attenuate protein synthesis in vitro and disrupt axon outgrowth in developing zebrafish. The FEBS journal. 288(1):142-159.
Abstract
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.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping