Assessing the Structures and Interactions of γD-Crystallin Deamidation Variants

Cataracts involve the deposition of the crystallin proteins in the vertebrate eye lens, causing opacification and blindness. They are associated with either genetic mutation or protein damage that accumulates over the lifetime of the organism. Deamidation of Asn residues in several different crystallins has been observed and is frequently invoked as a cause of cataract. Here, we investigated the properties of Asp variants, deamidation products of gamma D-crystallin, by solution NMR, X-ray crystallography, and other biophysical techniques. No substantive structural or stability changes were noted for all seven Asn to Asp gamma D-crystallins. Importantly, no changes in diffusion interaction behavior could be detected. Our combined experimental results demonstrate that introduction of single Asp residues on the surface of gamma D-crystallin by deamidation is unlikely to be the driver of cataract formation in the eye lens.

Automated summary

Research shows that introducing single Asp residues on the surface of γD-crystallin by deamidation is unlikely to drive cataract formation in the eye lens.