Michler's hydrol blue elucidates structural differences in prion strains
Artikel i vetenskaplig tidskrift, 2020

Yeast prions provide self-templating protein-based mechanisms of inheritance whose conformational changes lead to the acquisition of diverse new phenotypes. The best studied of these is the prion domain (NM) of Sup35, which forms an amyloid that can adopt several distinct conformations (strains) that confer distinct phenotypes when introduced into cells that do not carry the prion. Classic dyes, such as thioflavin T and Congo red, exhibit large increases in fluorescence when bound to amyloids, but these dyes are not sensitive to local structural differences that distinguish amyloid strains. Here we describe the use of Michler's hydrol blue (MHB) to investigate fibrils formed by the weak and strong prion fibrils of Sup35NM and find that MHB differentiates between these two polymorphs. Quantum mechanical time-dependent density functional theory (TDDFT) calculations indicate that the fluorescence properties of amyloid-bound MHB can be correlated to the change of binding site polarity and that a tyrosine to phenylalanine substitution at a binding site could be detected. Through the use of site-specific mutants, we demonstrate that MHB is a site-specific environmentally sensitive probe that can provide structural details about amyloid fibrils and their polymorphs.

Sup35NM

Prion

Amyloid dye

Amyloid fibril

Fluorescence spectroscopy

Författare

Yiling Xiao

UT Southwestern Medical Center

Sandra Rocha

Chalmers, Biologi och bioteknik, Kemisk biologi

Catherine Kitts

Chalmers, Kemi och kemiteknik, Kemi och biokemi, Fysikalisk kemi

Anna Reymer

Göteborgs universitet

Tamas Beke-Somfai

Magyar Tudomanyos Akademia

K. K. Frederick

UT Southwestern Medical Center

Bengt Nordén

Chalmers, Kemi och kemiteknik, Kemi och biokemi

Proceedings of the National Academy of Sciences of the United States of America

0027-8424 (ISSN) 1091-6490 (eISSN)

Vol. 117 47 29677-29683

Ämneskategorier

Biokemi och molekylärbiologi

Biofysik

Medicinsk bioteknologi (med inriktning mot cellbiologi (inklusive stamcellsbiologi), molekylärbiologi, mikrobiologi, biokemi eller biofarmaci)

DOI

10.1073/pnas.2001732117

PubMed

33168711

Mer information

Senast uppdaterat

2020-12-10