Transthyretin forms amyloid fibrils at physiological pH with ultrasonication.
In transthyretin (TTR)-related amyloidosis, wild-type TTR (WT-TTR), as well as mutated TTRs play important roles in the pathogenesis of senile systemic amyloidosis and familial amyloidotic polyneuropathy. However, WT-TTR usually forms stable tetramers at physiological pH, and the mechanism of such fibril formation under physiological conditions remains to be elucidated. In this study, we demonstrated WT-TTR amyloid fibril formation at physiological pH with ultrasonication. Cross-linked SDS-PAGE and circular dichroism revealed that ultrasonication induced both tetrameric TTR dissociation and monomeric TTR denaturation. These results indicate that extremely low pH is not an essential condition for TTR amyloid fibril formation if TTR is degenerated in such conditions. In addition, this method allows analysis of accelerator factors or inhibitory agents in TTR amyloid fibril formation at neutral pH.
Misumi
Yohei
Y
Department of Neurology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
Ueda
Mitsuharu
M
Fujimori
Hiromi
H
Shinriki
Satoru
S
Meng
Wei
W
Kim
Jaemi
J
Saito
Shiori
S
Obayashi
Konen
K
Uchino
Makoto
M
Ando
Yukio
Y
D000682:Amyloid / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D046529:Microscopy, Electron, Transmission; D046912:Multiprotein Complexes / Q000737:chemistry / Q000378:metabolism; D011228:Prealbumin / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D020836:Protein Structure, Quaternary; D013010:Sonication
D000682:Amyloid; D046912:Multiprotein Complexes; D011228:Prealbumin