Sequence analysis of betaA3, betaB3, and betaA4 crystallins completes the identification of the major proteins in young human lens.
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.
Lampi
K J
KJ
Department of Oral Molecular Biology, Oregon Health Sciences University, Portland, Oregon 97201, USA.
Ma
Z
Z
Shih
M
M
Shearer
T R
TR
Smith
J B
JB
Smith
D L
DL
David
L L
LL
D000595:Amino Acid Sequence; D001483:Base Sequence; D003459:Crystallins / Q000737:chemistry*; D018076:DNA, Complementary / Q000737:chemistry; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007223:Infant; D007908:Lens, Crystalline / Q000737:chemistry*; D008969:Molecular Sequence Data; D016339:Spectrometry, Mass, Fast Atom Bombardment; D038205:beta-Crystallin A Chain; D038206:beta-Crystallin B Chain
C489108:CRYBA1 protein, human; C103907:CRYBA4 protein, human; C103908:CRYBB3 protein, human; D003459:Crystallins; D018076:DNA, Complementary; D038205:beta-Crystallin A Chain; D038206:beta-Crystallin B Chain