Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.

BACKGROUND: Defects in protein folding may lead to severe degenerative diseases characterized by the appearance of amyloid fibril deposits. Cytotoxicity in amyloidoses has been linked to poration of the cell membrane that may involve interactions with amyloid intermediates of annular shape. Although...

Full description

Bibliographic Details
Main Authors: Ricardo H Pires, Árpád Karsai, Maria J Saraiva, Ana M Damas, Miklós S Z Kellermayer
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2012-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3440338?pdf=render
_version_ 1811325012988133376
author Ricardo H Pires
Árpád Karsai
Maria J Saraiva
Ana M Damas
Miklós S Z Kellermayer
author_facet Ricardo H Pires
Árpád Karsai
Maria J Saraiva
Ana M Damas
Miklós S Z Kellermayer
author_sort Ricardo H Pires
collection DOAJ
description BACKGROUND: Defects in protein folding may lead to severe degenerative diseases characterized by the appearance of amyloid fibril deposits. Cytotoxicity in amyloidoses has been linked to poration of the cell membrane that may involve interactions with amyloid intermediates of annular shape. Although annular oligomers have been detected in many amyloidogenic systems, their universality, function and molecular mechanisms of appearance are debated. METHODOLOGY/PRINCIPAL FINDINGS: We investigated with high-resolution in situ atomic force microscopy the assembly and disassembly of transthyretin (TTR) amyloid protofibrils formed of the native protein by pH shift. Annular oligomers were the first morphologically distinct intermediates observed in the TTR aggregation pathway. Morphological analysis suggests that they can assemble into a double-stack of octameric rings with a 16 ± 2 nm diameter, and displaying the tendency to form linear structures. According to light scattering data coupled to AFM imaging, annular oligomers appeared to undergo a collapse type of structural transition into spheroid oligomers containing 8-16 monomers. Disassembly of TTR amyloid protofibrils also resulted in the rapid appearance of annular oligomers but with a morphology quite distinct from that observed in the assembly pathway. CONCLUSIONS/SIGNIFICANCE: Our observations indicate that annular oligomers are key dynamic intermediates not only in the assembly but also in the disassembly of TTR protofibrils. The balance between annular and more compact forms of aggregation could be relevant for cytotoxicity in amyloidogenic disorders.
first_indexed 2024-04-13T14:25:39Z
format Article
id doaj.art-cb48f66acfdd4148aba8ba37f096c1b7
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-13T14:25:39Z
publishDate 2012-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-cb48f66acfdd4148aba8ba37f096c1b72022-12-22T02:43:20ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-0179e4499210.1371/journal.pone.0044992Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.Ricardo H PiresÁrpád KarsaiMaria J SaraivaAna M DamasMiklós S Z KellermayerBACKGROUND: Defects in protein folding may lead to severe degenerative diseases characterized by the appearance of amyloid fibril deposits. Cytotoxicity in amyloidoses has been linked to poration of the cell membrane that may involve interactions with amyloid intermediates of annular shape. Although annular oligomers have been detected in many amyloidogenic systems, their universality, function and molecular mechanisms of appearance are debated. METHODOLOGY/PRINCIPAL FINDINGS: We investigated with high-resolution in situ atomic force microscopy the assembly and disassembly of transthyretin (TTR) amyloid protofibrils formed of the native protein by pH shift. Annular oligomers were the first morphologically distinct intermediates observed in the TTR aggregation pathway. Morphological analysis suggests that they can assemble into a double-stack of octameric rings with a 16 ± 2 nm diameter, and displaying the tendency to form linear structures. According to light scattering data coupled to AFM imaging, annular oligomers appeared to undergo a collapse type of structural transition into spheroid oligomers containing 8-16 monomers. Disassembly of TTR amyloid protofibrils also resulted in the rapid appearance of annular oligomers but with a morphology quite distinct from that observed in the assembly pathway. CONCLUSIONS/SIGNIFICANCE: Our observations indicate that annular oligomers are key dynamic intermediates not only in the assembly but also in the disassembly of TTR protofibrils. The balance between annular and more compact forms of aggregation could be relevant for cytotoxicity in amyloidogenic disorders.http://europepmc.org/articles/PMC3440338?pdf=render
spellingShingle Ricardo H Pires
Árpád Karsai
Maria J Saraiva
Ana M Damas
Miklós S Z Kellermayer
Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
PLoS ONE
title Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
title_full Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
title_fullStr Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
title_full_unstemmed Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
title_short Distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils.
title_sort distinct annular oligomers captured along the assembly and disassembly pathways of transthyretin amyloid protofibrils
url http://europepmc.org/articles/PMC3440338?pdf=render
work_keys_str_mv AT ricardohpires distinctannularoligomerscapturedalongtheassemblyanddisassemblypathwaysoftransthyretinamyloidprotofibrils
AT arpadkarsai distinctannularoligomerscapturedalongtheassemblyanddisassemblypathwaysoftransthyretinamyloidprotofibrils
AT mariajsaraiva distinctannularoligomerscapturedalongtheassemblyanddisassemblypathwaysoftransthyretinamyloidprotofibrils
AT anamdamas distinctannularoligomerscapturedalongtheassemblyanddisassemblypathwaysoftransthyretinamyloidprotofibrils
AT miklosszkellermayer distinctannularoligomerscapturedalongtheassemblyanddisassemblypathwaysoftransthyretinamyloidprotofibrils