| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2005: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2004: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
|---|
| Research Abstract |
Protein kinase C (PKC) is an unique enzyme which is activated by calcium ion and lipids such as phosphatidylserine, 1,2-diacylglycerol, free fatty acids, and lysophosphatidylcholine. It is well known that PKC plays a crucial role in receptor-mediated signal transduction affecting diverse range of cellular responses such as cell proliferation, differentiation, hormonal action and neurotransmission. On the other hand, various reports indicate that PKC molecules also participate in pathological processes such as tumor promotion, inflammation, autoimmune diseases, atherosclerosis and neurodegenerative disorder. We have demonstrated that oxidized-diacylglycerol (DAG-OOH) activates rat brain PKC as efficiently as phorbol ester (PMA), artificial and powerful activator for PKC. This result markedly suggested that DAG-OOH might act as a biological messenger in oxidative stress to efficiently alter the PKC-dependent signal transduction system to a similar extent to PMA. Furthermore, DAG-OOH injured the cultured neurons with the over-activation of PKC delta and MAP kinase. Among these studies, it has been suspected that unknown PKC isoforms (PKC-X), which is more susceptible to DAG-OOH than other PKC isoforms, exist in rat brain homogenate. PKC-X is thought to be the importance role for the DAG-OOH-induced neuronal cell injury. In the present study, we attempt to identify PKC-X from rat brain homogenate. The fraction that had a high concentration of PKC-X protein was separated from brain homogenate by DEAE-sephacel column chromatography. Using Biacore device that be able to analyze the molecular- molecular interaction, it became apparent that this fraction highly containing PKC-X exhibited particular affinity to DAG-OOH.
|
