Sequence analysis of betaA3, betaB3, and betaA4 crystallins completes the identification of the major proteins in young human lens.
Lampi K.J., Ma Z., Shih M., Shearer T.R., Smith J.B., Smith D.L., David L.L.
A combination of Edman sequence analysis and mass spectrometry identified the major proteins of the young human lens as alphaA, alphaB, betaA1, betaA3, betaA4, betaB1, betaB2, betaB3, gammaS, gammaC, and gammaD-crystallins and mapped their positions on two-dimensional electrophoretic gels. The primary structures of human betaA1, betaA3, betaA4, and betaB3-crystallin subunits were predicted by determining cDNA sequences. Mass spectrometric analyses of each intact protein as well as the peptides from trypsin-digested proteins confirmed the predicted amino acid sequences and detected a partially degraded form of betaA3/A1 missing either 22 or 4 amino acid residues from its N-terminal extension. These studies were a prerequisite for future studies to determine how human lens proteins are altered during aging and cataract formation.
J. Biol. Chem. 272:2268-2275(1997) [ PubMed | SRS | CiteXplore ]
