TY - JOUR
T1 - Age-related changes of alpha-crystallin aggregate in human lens
AU - Fujii, N.
AU - Shimmyo, Y.
AU - Sakai, M.
AU - Sadakane, Y.
AU - Nakamura, T.
AU - Morimoto, Y.
AU - Kinouchi, T.
AU - Goto, Y.
AU - Lampi, K.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/1
Y1 - 2007/1
N2 - Lens alpha-crystallin, composed of two subunits alpha A- and alpha B-crystallin, forms large aggregates in the lens of the eye. The present study investigated the aggregate of human lens alpha-crystallin from elderly and young donors. Recombinant alpha A- and alpha B-crystallins in molar ratios of alpha A to alpha B at 1:1, corresponding to the aged sample, were also studied in detail. We found by ultra-centrifugation analysis that the alpha-crystallin aggregate from elderly donors was large and heterogeneous with an average sedimentation coefficient of 30 S and a range of 20-60 S at 37 °C. This was higher compared to the young samples that had an average sedimentation coefficient of 17 S. The sedimentation coefficients of recombinant alpha A- and alpha B-crystallins were approximately 12 S and 15 S, respectively. Even when recombinant alpha-crystallins were mixed in molar ratios equivalent to those found in vivo, similar S values as the native aged alpha-crystallin aggregates were not obtained. Changes in the self-association of alpha-crystallin aggregate were correlated to changes in chaperone activity. Alpha-crystallin from young donors, and recombinant alpha A- and alpha B-crystallin and their mixtures showed chaperone activity, which was markedly lost in samples from the aged alpha-crystallin aggregates.
AB - Lens alpha-crystallin, composed of two subunits alpha A- and alpha B-crystallin, forms large aggregates in the lens of the eye. The present study investigated the aggregate of human lens alpha-crystallin from elderly and young donors. Recombinant alpha A- and alpha B-crystallins in molar ratios of alpha A to alpha B at 1:1, corresponding to the aged sample, were also studied in detail. We found by ultra-centrifugation analysis that the alpha-crystallin aggregate from elderly donors was large and heterogeneous with an average sedimentation coefficient of 30 S and a range of 20-60 S at 37 °C. This was higher compared to the young samples that had an average sedimentation coefficient of 17 S. The sedimentation coefficients of recombinant alpha A- and alpha B-crystallins were approximately 12 S and 15 S, respectively. Even when recombinant alpha-crystallins were mixed in molar ratios equivalent to those found in vivo, similar S values as the native aged alpha-crystallin aggregates were not obtained. Changes in the self-association of alpha-crystallin aggregate were correlated to changes in chaperone activity. Alpha-crystallin from young donors, and recombinant alpha A- and alpha B-crystallin and their mixtures showed chaperone activity, which was markedly lost in samples from the aged alpha-crystallin aggregates.
KW - Aggregation
KW - Aging
KW - Analytical ultracentrifugation
KW - Lens alpha-crystallin
UR - http://www.scopus.com/inward/record.url?scp=33845268860&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33845268860&partnerID=8YFLogxK
U2 - 10.1007/s00726-006-0303-4
DO - 10.1007/s00726-006-0303-4
M3 - Article
C2 - 16699822
AN - SCOPUS:33845268860
SN - 0939-4451
VL - 32
SP - 87
EP - 94
JO - Amino Acids
JF - Amino Acids
IS - 1
ER -