Insights into the biochemical and biophysical mechanisms mediating the longevity of the transparent optics of the eye lens

A summary of key factors needed in the development and maintenance of transparency and optical properties in the aging lens is seen in Figure 8. Interactions at the molecular and cellular levels account for the formation of the transparent symmetric optics that contribute to the refractive properties of the living “refracton” in the eye. Their significance for visual function cannot be overstated. From the perspective of global health, these factors can impact progress on novel therapeutics to preserve and improve vision, specifically in aging populations. As a challenging scientific problem, the biology of interactions between light waves and organic matter is the basis of transparent extracellular and cellular tissues. Systematic studies are providing new knowledge about membrane, cytoskeletal, and cytoplasmic adaptations, which generate the image-forming refracton and how it is maintained and matures over a lifetime. The signaling mechanisms that synchronize proliferation, migration, elongation, and maintenance as a highly symmetric optically transparent tissue are unique to the lens. The lens is a valuable model for the study of both cellular and molecular longevity. This is particularly true with respect to protein stabilization mechanisms involving PTMs, because the very long-lived proteins are not replaced as in other nontransparent tissues.Figure 8Key factors in the development and aging of the transparent lens. The systematic review of recent and past advances in lens and cataract research provides insight into the significance of biochemical and biophysical control of lens short-range order (SRO), transparency, and symmetry during aging. Note: While image formation is largely a function of symmetry and refractive index, transparency is linked closely to membrane, protein, and cytoplasmic structure, supported by a unique microcirculation, metabolism, and biochemistry. 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