Modulation of the chaperone-like activity of bovine α-crystallin

Modulation of the chaperone-like activity of bovine α-crystallin

John I. Clark* and
Qing-ling Huang†

^*357420 Biological Structure and Ophthalmology, University of Washington, Seattle, WA 98195-7420; and ^†Jules Stein Institute, University of California, Los Angeles, School of Medicine, Los Angeles, CA 90024-7008

Abstract

The effects of pantethine, glutathione, and selected chemical reagents on the anti-aggregation activity of α-crystallin was evaluated. Protein aggregation was monitored by light scattering of solutions of denatured β_L-crystallin or alcohol dehydrogenase (ADH). The ratios of β_L-crystallin/α-crystallin and ADH/α-crystallin were adjusted so that partial inhibition of protein aggregation at 60°C or 37°C, respectively, was observed and modulation of the chaperone action of α-crystallin could be evaluated easily with selected endogenous metabolites. Enhancement of the anti-aggregation activity in the β_L-crystallin assay was strongest with pantethine, which appeared to interact with α-crystallin. Enhancement of the anti-aggregation activity in the ADH assay was strongest with glutathione which appeared to interact with ADH. The results indicated that the products of common metabolic pathways can modulate the chaperone-like effects of α-crystallin on protein aggregation.

Footnotes

George B. Benedek, Massachusetts Institute of Technology, Cambridge, MA
Abbreviations: ADH, alcohol dehydrogenase; DTT, dithiothreitol; GSH, reduced glutathione.