Amyloid-like Prep1 peptides exhibit reversible blue-green-red fluorescence in vitro and in living cells

PREP1-based peptides form amyloid-like aggregates endowed with an intrinsic blue-green-red fluorescence with an unusual sharp maximum at 520 nm upon excitation with visible light under physiological conditions. The peptide PREP1[117-132], whose sequence does not contain aromatic residues, presents a pH-dependent and reversible fluorescence, in line with its structural transition from beta-sheet rich aggregates to alpha-helix structures. These findings further demonstrate that the non-canonical fluorescence exhibited by amyloids is an articulated phenomenon.

Automated summary

Peptides based on PREP1 can form amyloid-like aggregates with unique spectral properties under physiological conditions, exhibiting pH-dependent and reversible fluorescence during the structural transition from beta-sheet rich aggregates to alpha-helix structures. These findings demonstrate that the non-canonical fluorescence exhibited by amyloids is a complex phenomenon.