Amyloid Fiber Formation in Human γD-Crystallin Induced by UV–B Photodamage
Year: 2013
Type: article
Abstract: γD-Crystallin is an abundant structural protein of the lens that is found in native and modified forms in cataractous aggregates. We establish that UV-B irradiation of γD-Crystallin leads to structurally specific modifications and precipitation via two mechanisms: amorphous aggregates and amyloid fibers. UV-B radiation causes cleavage of the backbone, in large measure near the interdomain interface, where side chain oxidations are also concentrated. 2D IR spectroscopy and expressed protein ligation localize fiber formation exclusively to the C-terminal domain of γD-Crystallin. The native β-sandwich domains are not retained upon precipitation by either mechanism. The similarities between the amyloid forming pathways when induced by either UV-B radiation or low pH suggest that the propensity for the C-terminal β-sandwich domain to form amyloid β-sheets determines the misfolding pathway independent of the mechanism of denaturation.
Source: Biochemistry
DOI: 10.1021/bi4008353
Institutions: University of Wisconsin–Madison, Oberlin College
Language: English
Topic: Connexins and lens biology
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2001952240