| Autor: |
Chen Y; Stroke Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-4128, USA., Matsushita M, Nairn AC, Damuni Z, Cai D, Frerichs KU, Hallenbeck JM |
| Jazyk: |
angličtina |
| Zdroj: |
Biochemistry [Biochemistry] 2001 Sep 25; Vol. 40 (38), pp. 11565-70. |
| DOI: |
10.1021/bi010649w |
| Abstrakt: |
Previously, eEF-2 phosphorylation has been identified as a reversible mechanism involved in the inhibition of the elongation phase of translation. In this study, an increased level of phosphorylation of eukaryotic elongation factor-2 (eEF-2) was observed in the brains and livers of hibernating ground squirrels. In brain and liver from hibernators, eEF-2 kinase activity was increased relative to that of active animals. The activity of protein phosphatase 2A (PP2A), a phosphatase that dephosphorylates eEF-2, was also decreased in brain and liver from hibernators. This was associated with an increase in the level of inhibitor 2 of PP2A (I(2)(PP2A)), although there was an increase in the level of the catalytic subunit of PP2A (PP2A/C) in hibernating brains and livers. These results indicate that eEF-2 phosphorylation represents a specific and previously uncharacterized mechanism for inhibition of the elongation phase of protein synthesis during hibernation. Increased levels of eEF-2 phosphorylation in hibernators appear to be a component of the regulated shutdown of cellular functions that permits hibernating animals to tolerate severe reductions in cerebral blood flow and oxygen delivery capacity. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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