Eye patches: Protein assembly of index-gradient squid lenses.
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ABSTRACT:
SUBMITTER: Cai J
PROVIDER: S-EPMC5682922 | biostudies-literature | 2017 Aug
REPOSITORIES: biostudies-literature
Publications
Eye patches: Protein assembly of index-gradient squid lenses.
Cai J J Townsend J P JP Dodson T C TC Heiney P A PA Sweeney A M AM
Science (New York, N.Y.) 20170801 6351
A parabolic relationship between lens radius and refractive index allows spherical lenses to avoid spherical aberration. We show that in squid, patchy colloidal physics resulted from an evolutionary radiation of globular S-crystallin proteins. Small-angle x-ray scattering experiments on lens tissue show colloidal gels of S-crystallins at all radial positions. Sparse lens materials form via low-valence linkages between disordered loops protruding from the protein surface. The loops are polydisper ...[more]
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