Single Acetylation-mimetic Mutation in TDP-43 Nuclear Localization Signal Disrupts Importin α1/β Signaling
[Display omitted] •Single acetylation mimetic mutation in the NLS mislocalizes TDP-43 in SH-SY5Y neuroblastoma cells.•Single acetylation mimetic mutation in the NLS disrupts binding to importin α1/β in vitro.•Both importin α1/β and free importin β exert anti-aggregation activity toward TDP-43 in vit...
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Published in | Journal of molecular biology Vol. 436; no. 20; p. 168751 |
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Main Authors | , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier Ltd
15.10.2024
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Subjects | |
Online Access | Get full text |
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Summary: | [Display omitted]
•Single acetylation mimetic mutation in the NLS mislocalizes TDP-43 in SH-SY5Y neuroblastoma cells.•Single acetylation mimetic mutation in the NLS disrupts binding to importin α1/β in vitro.•Both importin α1/β and free importin β exert anti-aggregation activity toward TDP-43 in vitro.•Importin α1/β bound to TDP-43 adopts an elongated structure.
Cytoplasmic aggregation of the TAR-DNA binding protein of 43 kDa (TDP-43) is the hallmark of sporadic amyotrophic lateral sclerosis (ALS). Most ALS patients with TDP-43 aggregates in neurons and glia do not have mutations in the TDP-43 gene but contain aberrantly post-translationally modified TDP-43. Here, we found that a single acetylation-mimetic mutation (K82Q) near the TDP-43 minor Nuclear Localization Signal (NLS) box, which mimics a post-translational modification identified in an ALS patient, can lead to TDP-43 mislocalization to the cytoplasm and irreversible aggregation. We demonstrate that the acetylation mimetic disrupts binding to importins, halting nuclear import and preventing importin α1/β anti-aggregation activity. We propose that perturbations near the NLS are an additional mechanism by which a cellular insult other than a genetically inherited mutation leads to TDP-43 aggregation and loss of function. Our findings are relevant to deciphering the molecular etiology of sporadic ALS. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0022-2836 1089-8638 1089-8638 |
DOI: | 10.1016/j.jmb.2024.168751 |