• Mishra S, Stein RA, McHaourab HS. Cataract-linked γD-crystallin mutants have weak affinity to lens chaperones α-crystallins. FEBS letters. 2012 Feb 17;586(4). 330-6. PMID: 22289178 [PubMed]. PMCID: PMC3282170. NIHMSID: NIHMS353137.


To test the hypothesis that α-crystallin chaperone activity plays a central role in maintenance of lens transparency, we investigated its interactions with γ-crystallin mutants that cause congenital cataract in mouse models. Although the two substitutions, I4F and V76D, stabilize a partially unfolded γD-crystallin intermediate, their affinities to α-crystallin are marginal even at relatively high concentrations. Detectable binding required further reduction of γD-crystallin stability which was achieved by combining the two mutations. Our results demonstrate that mutants and possibly age-damaged γ-crystallin can escape quality control by lens chaperones rationalizing the observation that they nucleate protein aggregation and lead to cataract.