エリトロサイトGlut1は,ビタミンCを合成することができない哺乳類でデヒドロアスコルビック酸の吸収を誘発する
Amélie Montel-Hagen1, Sandrina Kinet, Nicolas Manel
1Institut de Génétique Moléculaire de Montpellier, CNRS, Université Montpellier I and II, Montpellier, France.
Cell
|March 25, 2008
まとめ
人間の赤血球は,発達中にグルト1経由でビタミンC前駆体 (DHA) を運ぶが,グルコース経由では運ばない. これは,スタマチン調節を含むビタミンCの合成不能を補償する.
科学分野:
- 細胞生物学 細胞生物学
- バイオケミストリー バイオケミストリー
- 人間の生理学 人間生理学
背景:
- 人間の赤血球は,最も高いレベルのグルコーストランスポーターGlut1を示しています.
- 赤血球発育 (エリトロポエーゼス) 中のGlut1の役割と調節は不明である.
研究 の 目的:
- ヒトのエリトプロエゼスにおけるGlut1の機能と調節を調査する.
- 発達中の赤血球における栄養素輸送の変化の背後にあるメカニズムを決定する.
主な方法:
- エリトロポエシス中のGlut1トランスクリプトレベルとグルコース/DHA輸送の分析.
- 赤血球の輸送に関与する調節タンパク質の識別.
主要な成果:
- 血糖の輸送は,Glut1のトランスクリプトが増加したにもかかわらず,エリトロポエーシス中に減少します.
- L-デヒドロアスコルビック酸 (DHA) 輸送は,スタモチンによって調節され,著しく強化されます.
- 赤血球Glut1とDHAの吸収は,ヒトとビタミンC合成が欠けている哺乳類に特異的です.
結論:
- エリトロサイトGlut1とストマチン共発現は,ビタミンC合成欠乏症の補償メカニズムである.
- これは,ヒトの赤血球が栄養素を輸送するためのユニークな適応を強調しています.
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