Identification of key regions and residues controlling Aβ folding and assembly.

ABSTRACT: Amyloid β-protein (Aβ) assembly is hypothesized to be a seminal neuropathologic event in Alzheimer's disease (AD). We used an unbiased D-amino acid substitution strategy to determine structure-assembly relationships of 76 different Aβ40 and Aβ42 peptides. We determined the effects of the substitutions on peptide oligomerization, secondary structure dynamics, fibril assembly dynamics, and fibril morphology. Our experiments revealed that the assembly of Aβ42 was more sensitive to chiral substitutions than was Aβ40 assembly. Substitutions at identical positions in the two peptides often, but not always, produced the same effects on assembly. Sites causing substantial effects in both Aβ40 and Aβ42 include His14, Gln15, Ala30, Ile31, Met35, and Val36. Sites whose effects were unique to Aβ40 inc

SUBMITTER: Hayden EY 

PROVIDER: S-EPMC5626695 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature