Studies on β crystallin from primate lens

The major β crystallin fractions from the human lens and the lenses of other selected primates have been isolated and partially characterized. Primate β crystallins, like those of most other mammals, consist of two heterogeneous protein fractions (βH and βL) of quite different molecular size. Most of the polypeptide chains comprising the βH and βL heteropolymers are common to both fractions. Evidence is presented suggesting that primate βH crystallin may be smaller than βH frm other vertebrate species. Additionally, human βH is found to contain a major component on sodium dodecyl sulfate (SDS) electrophoresis which is much larger (about 60,000 daltons) than other β crystallin polypeptides. Immunochemical evidence indicates that some components of primate crystallin have evolved rapidly, although at least one antigenic component is very conservative and gives a reaction of identity with all other vertebrate β crystallins studied.