Cataracts, the clouding of the eye lens, is a leading cause of blindness and visual impairments worldwide. Cataracts form when oxidative stress in the lens causes lens proteins, such as crystallin, to destabilise and aggregate. The molecular basis for the oxidation-induced aggregation of these proteins, however, has remained elusive. In this paper, recently published in the Journal of Molecular Biology, we use X-ray crystallography and small-angle X-ray light scattering to describe the structure of a disulfide-linked dimer of human gammaS-crystallin. This disulfide-linked dimer is prone to forming aggregates and would likely be prevalent in aging eyes. These findings provide insight into how oxidative modification of crystallins contributes to cataract formation.
This work was a collaboration with, and led by, members of the Carver Group at the Australian National University. Congratulations to all involved!