Project Summary/Abstract Lens crystallin aggregation and precipitation is the primary cause for cataract formation. A cataract occurs when the lens α-crystallin ceases to perform its chaperone function of aiding in maintaining lens transparency. During the course of studies performed on lens crystallin chaperone function, discovered were specific sequences in αA- and αB-crystallin responsible for the chaperone function. In addition, a deletion mutant of αB-crystallin (B∆54-61) with a ~10-fold increase in chaperone function during in vitro protein aggregation assays were developed, suggesting that this recombinant crystallin can be considered a “super chaperone.” Protein misfolding and aggregation is the primary cause of Alzheimer's disease (AD), Parkinson's disease, Huntington's disease, Creutzfeldt-Jakob disease, and many other degenerative and neurodegenerative disorders. Based on the studies conducted with unfolding model substrates, the preliminary data included in this supplementary request show the “αB∆54-61 super chaperone” developed can alleviate A-induced paralysis and extend the lifespan in AD model of C. elegans (CL4176) expressing A-peptide. With supplement award support, it is proposed to test the efficacy of “super chaperones” in protecting neural cells and C. elegans from β-amyloid (and α-synuclein) aggregation-induced toxicity. Previously shown, crystallin peptide chaperone that encapsulates the chaperone site in αA-crystallin and a cell penetrable form of the same (with superior chaperone activity compared to the original mini-chaperone) suppresses β- amyloid fibril formation and toxicity in vitro. The “super chaperones” also protect ARPE-19 and Cos-7 cells from oxidative stress-induced apoptosis. Our studies suggest that the “super chaperones” developed could be used as therapeutics against diseases involving protein aggregation, oxidative stress, and apoptosis. It is proposed to carry out a systematic study to test the efficacy of peptide chaperones to suppress amyloid aggregation and toxicity using in vitro experiments, cell culture systems (ARPE-19 cells, N-27 cells and primary neuronal cells) and in AD model of C. elegans (CL4176). Thus, studies carried out with supplementary funds to the parent grant will help to develop crystallin based proteins/mini-chaperones that have therapeutic value. The study will open new avenues for treating AD and related dementias. The long-term goals of our studies are to develop α-crystallin-based protein and peptide chaperones having therapeutic value. A supplementary award to the current project, R01 EY023219 - Metastable crystallins- Structure and Stabilization, will help to expand the study currently focused on protein aggregation diseases of the eye, to protein misfolding diseases of the brain and other tissues, which share a common etiology to the protein misfolding diseases of the eye. Once the beneficial effects of the “super chaperones” in the proposed systems are demonstrated, a p...