Send to

Choose Destination
FEBS Lett. 2007 May 15;581(10):1939-43. Epub 2007 Apr 13.

Specificity of alphaA-crystallin binding to destabilized mutants of betaB1-crystallin.

Author information

Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA.


To elucidate the structural and energetic basis of attractive protein interactions in the aging lens, we investigated the binding of destabilized mutants of betaB1-crystallin to the lens chaperones, alpha-crystallins. We show that the mutations enhance the binding affinity to alphaA- but not alphaB-crystallin at physiological temperatures. Complex formation disrupts the dimer interface of betaB1-crystallin consistent with the binding of a monomer. Binding isotherms obtained at increasing concentrations of betaB1-crystallin deviate from a classic binding equilibrium and display cooperative-like behavior. In the context of betaB1-crystallin unfolding equilibrium, these characteristics are reflective of the concentration-dependent change in the population of a dimeric intermediate that has low affinity to alphaA-crystallin. In the lens, where alpha-crystallin binding sites are not regenerated, this may represent an added mechanism to maintain lens transparency.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center