Protection against molecular aging and degeneration

Image formation in vertebrate vision depends on transmission and focusing of light by the biological lens. The biophysical properties of visible light constrain the differentiation of cells in the embryonic surface ectoderm during the formation of symmetric, concentric, transparent layers of variable index of refraction. In the absence of turnover, lens cells and their molecular constituents are retained for the lifetime of the individual and a robust biological mechanism is necessary to protect against protein aggregation resulting from the cellular stress of aging. AlphaB crystallin is part of a selective rather than specific mechanism for recognition of protein instability. Patterns of interactive sequences recognize surface instabilities responsible for the self assembly of normal intracellular filaments or abnormal fibrils and aggregates. There is much to learn about the cooperative nature of the interactive surface domains both in the normal assembly of structural proteins and in the self assembly of abnormal fibrils and aggregates. Supported by EY04542 from the N.E.I.