Puzzle of crystallin diversity in eye lenses.

Laboratory of Molecular and Developmental Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892.

Crystallins have evolved by various mechanisms that are associated with high expression of their genes in the eye lens. The diversity and pattern of crystallins among different species indicate that independent events have occurred at the molecular level during the evolution of the lens in different invertebrates (jellyfish, squid, and octopus) and vertebrates. Although it is possible that different crystallins are needed to fulfill the specific needs of individual species, the unexpectedly large array of proteins that function as crystallins and their abundance in the lens raise the possibility that selective pressures optimizing the function of certain transcription factors in the lens contribute to the recruitment of crystallins.

PMID: 8219350 [PubMed - indexed for MEDLINE]