An ALS-linked mutation in TDP-43 disrupts normal protein interactions in the motor neuron response to oxidative stress.
Neurobiol Dis
; 144: 105050, 2020 10.
Article
en En
| MEDLINE
| ID: mdl-32800996
ABSTRACT
TDP-43 pathology is a key feature of amyotrophic lateral sclerosis (ALS), but the mechanisms linking TDP-43 to altered cellular function and neurodegeneration remain unclear. We have recently described a mouse model in which human wild-type or mutant TDP-43 are expressed at low levels and where altered stress granule formation is a robust phenotype of TDP-43M337V/- expressing cells. In the present study we use this model to investigate the functional connectivity of human TDP-43 in primary motor neurons under resting conditions and in response to oxidative stress. The interactome of human TDP-43WT or TDP-43M337V was compared by mass spectrometry, and gene ontology enrichment analysis identified pathways dysregulated by the M337V mutation. We found that under normal conditions the interactome of human TDP-43WT was enriched for proteins involved in transcription, translation and poly(A)-RNA binding. In response to oxidative stress, TDP-43WT recruits proteins of the endoplasmic reticulum and endosomal-extracellular transport pathways, interactions which are reduced in the presence of the M337V mutation. Specifically, TDP-43M337V impaired protein-protein interactions involved in stress granule formation including reduced binding to the translation initiation factors Poly(A)-binding protein and Eif4a1 and the endoplasmic reticulum chaperone Grp78. The M337V mutation also affected interactions involved in endosomal-extracellular transport and this this was associated with reduced extracellular vesicle secretion in primary motor neurons from TDP-43M337V/- mice and in human iPSCs-derived motor neurons. Taken together, our analysis highlights a TDP-43 interaction network in motor neurons and demonstrates that an ALS associated mutation may alter the interactome to drive aberrant pathways involved in the pathogenesis of ALS.
Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Estrés Oxidativo
/
Proteínas de Unión al ADN
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Redes Reguladoras de Genes
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Mapas de Interacción de Proteínas
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Esclerosis Amiotrófica Lateral
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Neuronas Motoras
Tipo de estudio:
Prognostic_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Neurobiol Dis
Asunto de la revista:
NEUROLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Reino Unido