Heat-induced conformational change of human lens recombinant alphaA- and alphaB-crystallins.
Mol Vis
; 6: 10-4, 2000 Mar 02.
Article
em En
| MEDLINE
| ID: mdl-10706895
ABSTRACT
PURPOSE:
To determine which component of lens alpha-crystallin is responsible for heat-induced transition, conformational change and high molecular weight (HMW) aggregation.METHODS:
Recombinant alphaA- and alphaB-crystallins were used. Temperature dependent changes were probed by Trp fluorescence and circular dichroism (CD) measurements. HMW aggregates were induced by heating at 62 degrees C for 1-2 h and then cooling to room temperature. The nature of HMW aggregation was studied with fluorescent probes, 4,4'-dianilino-1, 1'-binaphthalene-5,5'-disulfonic acid (bis-ANS) and thioflavin T (ThT).RESULTS:
CD and Trp fluorescence revealed that alphaB-crystallin was more susceptible than alphaA-crystallin to heat-induced conformational change and aggregation. At temperatures greater than 70 degrees C, alphaB-crystallin precipitated but alphaA-crystallin remained soluble. Both bis-ANS and ThT probes displayed increased fluorescence intensity with HMW aggregation, but the increase for bis-ANS was greater with alphaB-crystallin than with alphaA-crystallin, while the reverse was true for ThT.CONCLUSIONS:
These results indicate that alphaB-crystallin is more susceptible than alphaA-crystallin to heat-induced conformational change and aggregation and are consistent with the notion that alphaA- and alphaB-crystallins have different biochemical and biophysical properties in spite of their high degree of homology.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cristalinas
/
Temperatura Alta
/
Cristalino
Limite:
Humans
Idioma:
En
Revista:
Mol Vis
Assunto da revista:
BIOLOGIA MOLECULAR
/
OFTALMOLOGIA
Ano de publicação:
2000
Tipo de documento:
Article
País de afiliação:
Estados Unidos