[Effects of aging and post-translational modifications on molecular chaperone-like activity of alpha-crystalline].
OBJECTIVE
To study the affects of aging and post-translational modifications in vitro on rabbit alpha-crystalline molecular chaperone-like activity.


METHODS
(1) Rabbits with three different ages (3 days old, 3 months old and 2 years old) were chosen in the study. The water-soluble crystalline in the three age groups was purified by Sephadex G-200 gel filtration. Different abilities of them to protect beta-low crystalline from thermal aggregation were observed. (2) Incubation of alpha-crystalline with fructose or with H(2)O(2) was carried out for 24 hours. Fructose was used for glycosylation and H(2)O(2) for oxidation of alpha-crystalline. Different abilities of modified and unmodified alpha-crystalline to protect beta-low crystalline from aggregation were observed.


RESULTS
(1) alpha-Crystalline of 3 months old rabbit has more ability to protect beta-low crystalline from aggregation than 2 years old rabbit but less ability than 3 days old rabbit. (2) The glycosylated and oxidized alpha-crystalline have less ability to protect beta-low crystalline from aggregation than the unmodified alpha-crystalline.


CONCLUSIONS
(1) With aging rabbit alpha-crystallines gradually lose their molecular chaperone-like ability. (2) The modified alpha-crystallines show the loss in molecular chaperone-like ability the most.
Department of Ophthalmology, The First Affiliated Hospital, Kunming Medical College, Kunming 650032, China. yxloculist@263.net
Xiaoli
X
Yang
Ronghan
R
Wu
Hanyu
H
Li
Lingbai
L
Zeng
Qiyun
Q
Mu
D000375:Aging / Q000378:metabolism*; D000818:Animals; D003459:Crystallins / Q000378:metabolism*; D006031:Glycosylation; D018832:Molecular Chaperones / Q000378:metabolism*; D010084:Oxidation-Reduction; D011485:Protein Binding / Q000502:physiology; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D011817:Rabbits
D003459:Crystallins; D018832:Molecular Chaperones