Amyloid β-Sheet Secondary Structure Identified in UV-Induced Cataracts of Porcine Lenses using 2D IR Spectroscopy.

ABSTRACT: Cataracts are formed by the aggregation of crystallin proteins in the eye lens. Many in vitro studies have established that crystallin proteins precipitate into aggregates that contain amyloid fibers when denatured, but there is little evidence that ex vivo cataracts contain amyloid. In this study, we collect two-dimensional infrared (2D IR) spectra on tissue slices of porcine eye lenses. As shown in control experiments on in vitro αB- and γD-crystallin, 2D IR spectroscopy can identify the highly ordered β-sheets typical of amyloid secondary structure even if the fibers themselves are too short to be resolved with TEM. In ex vivo experiments of acid-treated tissues, characteristic 2D IR features are observed and fibers >50nm in length are resolved by transmission electron microscopy (TEM),

SUBMITTER: Zhang TO 

PROVIDER: S-EPMC5493149 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature