| Project/Area Number |
06454694
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Nerve anatomy/Neuropathology
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| Research Institution | KYUSHU UNIVERSITY |
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Principal Investigator |
IWAKI Toru Kyushu University, Faculty of Medincine, Assoiciate Professor, 医学部, 助教授 (40221098)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥5,600,000 (Direct Cost: ¥5,600,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥4,800,000 (Direct Cost: ¥4,800,000)
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| Keywords | astrocyte / glia / alphaB-crystallin / heat shock / cytoskeleton / transfectin / 熱ショック蛋白質 / 中枢神経系 / アンチセンス核酸 / 遺伝子発現 |
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| Research Abstract |
It has been shown by immunohistochemical studies that alphaB-crystallin accumulated in the reactive and neoplastic glial cells in a variety of pathologic situations. We investigated the phenotypic effects of selectively altering the levels of alphaB-crystallin in cultured glial cells by genetic manipulation. Glioma cells were transfected with a rat alphaB-crystallin sense cDNA or an antisense cDNA to alter cellular levels of alphaB-crystallin. The anti-sense strategy resulted in decreased alphaB-crystallin levels, as revealed by Western blot and immunocytochemical analyzes. The reduced alphaBj-crystallin expression was accompanied by alterations in cellular phenotyp :
(1)a reduction of cell size and/or a slender cell mophology ; (2)a disorganized microfilament network ; and (3)a reduction of cell adhesiveness. Like HSP27, the presence of additional alphaB-crystallin protein confer a thermoresistant phenotype to stable transfectants. Thus, alphaB-crystallin inglioma cells plays a role in their thermal resistance and maycontribute to the stability of cytoskeletal organization. Next we investigated the influence of elevated extracellular K^+ on th expression of alphaB-crystallin in glial cells. The treatment of the glioma cells with augmented K^+ in the cultrue media induced an accumulation of alphaB-crystallin mRNA in a dose-dependent manner and an accumulation of the alphaB-crystallin as well. Furthermore, an overexpression of alphaB-crystallin in the transformant transfected with a rat alphaB-crystallin cDNA conferred a resistant phenotype against the insult of elevated extracellular K^+ on the glioma cells. Thus, alphaB-crystallin may contribute to the survival of reactive glia in the presence of a high extracellular K^+ concentration.
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