In Vitro and In Vivo Biochemical Analysis of F20E and I31E/E22G Aβ42
(A) F20E Aβ42 (blue squares) aggregates more slowly than WT Aβ42 (red circles), and both were found to have formed well-defined fibrils at the end point of this assay (Figure S3).
(B) Immunohistochemistry shows extensive Aβ42 deposition (brown staining) in the brain of WT-Aβ42--expressing flies at 20 d of age (arrows).
(C) In contrast, F20E Aβ42 flies show no evidence of Aβ42 deposition at 20 d of age.
(D) Both E22G (red circles) and I31E/E22G (blue squares) Aβ42 aggregate at similar rates as measured by Thioflavin T fluorescence.
(E) Aβ42 immunohistochemistry shows deposition throughout the cortex in the brain of E22G-Aβ42-expressing flies at 8 d of age (arrows). This deposition is also associated with the appearance of vacuoles (asterisks).
(F) Flies expressing I31E/E22G Aβ42 show extensive deposition of Aβ42 throughout their cortex (arrows). In contrast to (E), no evidence of neurodegeneration (vacuolation) is seen.
