ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.

TAR-DNA-binding protein-43 (TDP-43) C-terminus encodes a prion-like domain widely presented in RNA-binding proteins, which functions to form dynamic oligomers and also, amazingly, hosts most amyotrophic lateral sclerosis (ALS)-causing mutations. Here, as facilitated by our previous discovery, by cir...

Full description

Bibliographic Details
Main Authors: Liangzhong Lim, Yuanyuan Wei, Yimei Lu, Jianxing Song
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2016-01-01
Series:PLoS Biology
Online Access:https://doi.org/10.1371/journal.pbio.1002338
_version_ 1818589164441960448
author Liangzhong Lim
Yuanyuan Wei
Yimei Lu
Jianxing Song
author_facet Liangzhong Lim
Yuanyuan Wei
Yimei Lu
Jianxing Song
author_sort Liangzhong Lim
collection DOAJ
description TAR-DNA-binding protein-43 (TDP-43) C-terminus encodes a prion-like domain widely presented in RNA-binding proteins, which functions to form dynamic oligomers and also, amazingly, hosts most amyotrophic lateral sclerosis (ALS)-causing mutations. Here, as facilitated by our previous discovery, by circular dichroism (CD), fluorescence and nuclear magnetic resonance (NMR) spectroscopy, we have successfully determined conformations, dynamics, and self-associations of the full-length prion-like domains of the wild type and three ALS-causing mutants (A315E, Q331K, and M337V) in both aqueous solutions and membrane environments. The study decodes the following: (1) The TDP-43 prion-like domain is intrinsically disordered only with some nascent secondary structures in aqueous solutions, but owns the capacity to assemble into dynamic oligomers rich in β-sheet structures. By contrast, despite having highly similar conformations, three mutants gained the ability to form amyloid oligomers. The wild type and three mutants all formed amyloid fibrils after incubation as imaged by electron microscopy. (2) The interaction with nucleic acid enhances the self-assembly for the wild type but triggers quick aggregation for three mutants. (3) A membrane-interacting subdomain has been identified over residues Met311-Gln343 indispensable for TDP-43 neurotoxicity, which transforms into a well-folded Ω-loop-helix structure in membrane environments. Furthermore, despite having very similar membrane-embedded conformations, three mutants will undergo further self-association in the membrane environment. Our study implies that the TDP-43 prion-like domain appears to have an energy landscape, which allows the assembly of the wild-type sequence into dynamic oligomers only under very limited condition sets, and ALS-causing point mutations are sufficient to remodel it to more favor the amyloid formation or irreversible aggregation, thus supporting the emerging view that the pathologic aggregation may occur via the exaggeration of functionally important assemblies. Furthermore, the coupled capacity of TDP-43 in aggregation and membrane interaction may critically account for its high neurotoxicity, and therefore its decoupling may represent a promising therapeutic strategy to treat TDP-43 causing neurodegenerative diseases.
first_indexed 2024-12-16T09:36:18Z
format Article
id doaj.art-d9dfebfd282e457b98c744a0a3c90109
institution Directory Open Access Journal
issn 1544-9173
1545-7885
language English
last_indexed 2024-12-16T09:36:18Z
publishDate 2016-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Biology
spelling doaj.art-d9dfebfd282e457b98c744a0a3c901092022-12-21T22:36:24ZengPublic Library of Science (PLoS)PLoS Biology1544-91731545-78852016-01-01141e100233810.1371/journal.pbio.1002338ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.Liangzhong LimYuanyuan WeiYimei LuJianxing SongTAR-DNA-binding protein-43 (TDP-43) C-terminus encodes a prion-like domain widely presented in RNA-binding proteins, which functions to form dynamic oligomers and also, amazingly, hosts most amyotrophic lateral sclerosis (ALS)-causing mutations. Here, as facilitated by our previous discovery, by circular dichroism (CD), fluorescence and nuclear magnetic resonance (NMR) spectroscopy, we have successfully determined conformations, dynamics, and self-associations of the full-length prion-like domains of the wild type and three ALS-causing mutants (A315E, Q331K, and M337V) in both aqueous solutions and membrane environments. The study decodes the following: (1) The TDP-43 prion-like domain is intrinsically disordered only with some nascent secondary structures in aqueous solutions, but owns the capacity to assemble into dynamic oligomers rich in β-sheet structures. By contrast, despite having highly similar conformations, three mutants gained the ability to form amyloid oligomers. The wild type and three mutants all formed amyloid fibrils after incubation as imaged by electron microscopy. (2) The interaction with nucleic acid enhances the self-assembly for the wild type but triggers quick aggregation for three mutants. (3) A membrane-interacting subdomain has been identified over residues Met311-Gln343 indispensable for TDP-43 neurotoxicity, which transforms into a well-folded Ω-loop-helix structure in membrane environments. Furthermore, despite having very similar membrane-embedded conformations, three mutants will undergo further self-association in the membrane environment. Our study implies that the TDP-43 prion-like domain appears to have an energy landscape, which allows the assembly of the wild-type sequence into dynamic oligomers only under very limited condition sets, and ALS-causing point mutations are sufficient to remodel it to more favor the amyloid formation or irreversible aggregation, thus supporting the emerging view that the pathologic aggregation may occur via the exaggeration of functionally important assemblies. Furthermore, the coupled capacity of TDP-43 in aggregation and membrane interaction may critically account for its high neurotoxicity, and therefore its decoupling may represent a promising therapeutic strategy to treat TDP-43 causing neurodegenerative diseases.https://doi.org/10.1371/journal.pbio.1002338
spellingShingle Liangzhong Lim
Yuanyuan Wei
Yimei Lu
Jianxing Song
ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
PLoS Biology
title ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
title_full ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
title_fullStr ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
title_full_unstemmed ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
title_short ALS-Causing Mutations Significantly Perturb the Self-Assembly and Interaction with Nucleic Acid of the Intrinsically Disordered Prion-Like Domain of TDP-43.
title_sort als causing mutations significantly perturb the self assembly and interaction with nucleic acid of the intrinsically disordered prion like domain of tdp 43
url https://doi.org/10.1371/journal.pbio.1002338
work_keys_str_mv AT liangzhonglim alscausingmutationssignificantlyperturbtheselfassemblyandinteractionwithnucleicacidoftheintrinsicallydisorderedprionlikedomainoftdp43
AT yuanyuanwei alscausingmutationssignificantlyperturbtheselfassemblyandinteractionwithnucleicacidoftheintrinsicallydisorderedprionlikedomainoftdp43
AT yimeilu alscausingmutationssignificantlyperturbtheselfassemblyandinteractionwithnucleicacidoftheintrinsicallydisorderedprionlikedomainoftdp43
AT jianxingsong alscausingmutationssignificantlyperturbtheselfassemblyandinteractionwithnucleicacidoftheintrinsicallydisorderedprionlikedomainoftdp43