RRC ID 60006
著者 Petel Légaré V, Harji ZA, Rampal CJ, Allard-Chamard X, Rodríguez EC, Armstrong GAB.
タイトル Augmentation of spinal cord glutamatergic synaptic currents in zebrafish primary motoneurons expressing mutant human TARDBP (TDP-43).
ジャーナル Sci Rep
Abstract Though there is compelling evidence that de-innervation of neuromuscular junctions (NMJ) occurs early in amyotrophic lateral sclerosis (ALS), defects arising at synapses in the spinal cord remain incompletely understood. To investigate spinal cord synaptic dysfunction, we took advantage of a zebrafish larval model and expressed either wild type human TARDBP (wtTARDBP) or the ALS-causing G348C variant (mutTARDBP). The larval zebrafish is ideally suited to examine synaptic connectivity between descending populations of neurons and spinal cord motoneurons as a fully intact spinal cord is preserved during experimentation. Here we provide evidence that the tail-beat motor pattern is reduced in both frequency and duration in larvae expressing mutTARDBP. In addition, we report that motor-related synaptic depolarizations in primary motoneurons of the spinal cord are shorter in duration and fewer action potentials are evoked in larvae expressing mutTARDBP. To more thoroughly examine spinal cord synaptic dysfunction in our ALS model, we isolated AMPA/kainate-mediated glutamatergic miniature excitatory post-synaptic currents in primary motoneurons and found that in addition to displaying a larger amplitude, the frequency of quantal events was higher in larvae expressing mutTARDBP when compared to larvae expressing wtTARDBP. In a final series of experiments, we optogenetically drove neuronal activity in the hindbrain and spinal cord population of descending ipsilateral glutamatergic interneurons (expressing Chx10) using the Gal4-UAS system and found that larvae expressing mutTARDBP displayed abnormal tail-beat patterns in response to optogenetic stimuli and augmented synaptic connectivity with motoneurons. These findings indicate that expression of mutTARDBP results in functionally altered glutamatergic synapses in the spinal cord.
巻・号 9(1)
ページ 9122
公開日 2019-6-24
DOI 10.1038/s41598-019-45530-3
PII 10.1038/s41598-019-45530-3
PMID 31235725
PMC PMC6591224
MeSH Animals DNA-Binding Proteins / genetics* Electrophysiological Phenomena* Gene Expression Glutamic Acid / metabolism Humans Motor Neurons / cytology Motor Neurons / metabolism* Mutation* Spinal Cord / physiology* Synapses / metabolism Synapses / physiology* Zebrafish*
IF 4.011
引用数 1
リソース情報
ゼブラフィッシュ Tg(chx10:Gal4)