イシヅカ　ユウタ   Yuta Ishizuka   石塚　佑太    所属   川崎医科大学  医学部 基礎医学　病態代謝学    職種   講師
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Leucine induces phosphorylation and activation of p70S6K in cortical neurons via the system L amino acid transporter.
掲載誌名	正式名：Journal of neurochemistry 略　 称：J Neurochem ISSNコード：14714159/00223042
掲載区分	国外
出版社	WILEY
巻・号・頁	106(2),pp.934-42
著者・共著者	Yuta Ishizuka, Naomasa Kakiya, Hiroyuki Nawa, Nobuyuki Takei
担当区分	筆頭著者
発行年月	2008/07
概要	p70S6 kinase is a multipotent kinase that phosphorylates substrates in response to extracellular stimuli. This kinase activity inhibits apoptosis, regulates cell size and controls translation. In the CNS, p70S6K also participates in synaptic plasticity. In this study, we report that leucine, a branched-chain amino acid, induces phosphorylation and activation of p70S6 kinase in cortical neurons. Leucine also induces phosphorylation of S6 protein, a substrate of p70S6K. These effects of leucine are completely inhibited by rapamycin, consistent with mammalian target of rapamycin mediating p70S6 phosphorylation. Finally, we demonstrate that the action of leucine on cortical neurons is mediated by the system L amino acid transporter. Neurons express components of system L amino acid transporter LAT1, LAT2, and CD98. Leucine uptake and its effect on p70S6 kinase are both inhibited by a specific inhibitor of system L amino acid transporter. We propose that leucine plays important roles in regulating signaling by p70S6 kinase by acting as an intercellular communicator in the CNS.
DOI	10.1111/j.1471-4159.2008.05438.x
PMID	18435829