| Autor: |
Regini JW; The Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff CF10 3NB, UK. reginijw@cardiff.ac.uk, Grossmann JG, Burgio MR, Malik NS, Koretz JF, Hodson SA, Elliott GF |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of molecular biology [J Mol Biol] 2004 Mar 05; Vol. 336 (5), pp. 1185-94. |
| DOI: |
10.1016/S0022-2836(03)00814-3 |
| Abstrakt: |
Whole eye lens and alpha-crystallin gels and solutions were investigated using X-ray scattering techniques at temperatures ranging from 20 degrees C to 70 degrees C. In whole lens isolated in phosphate-buffered saline, the spacing of the dominant X-ray reflection seen with low-angle scattering was constant from 20 degrees C to 45 degrees C but increased at 50 degrees C from 15.2 nm to 16.5 nm. At room temperature, the small-angle X-ray diffraction pattern of the intact lens was very similar to the pattern of alpha-crystallin gels at near-physiological concentration (approximately 300 mg/ml), so it is reasonable to assume that the alpha-crystallin pattern dominates the pattern of the intact lens. Our results therefore indicate that in whole lens alpha-crystallin is capable of maintaining its structural properties over a wide range of temperature. This property would be useful in providing protection for other lens proteins super-aggregating. In the alpha-crystallin gels, a moderate increase in both the spacing and intensity of the reflection was observed from 20 degrees C to 45 degrees C, followed by an accelerated increase from 45 degrees C to 70 degrees C. Upon cooling, this effect was found to be irreversible over 11 hours. Qualitatively similar results were observed for alpha-crystallin solutions at a variety of lower concentrations. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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Full Text from ScienceDirect