ADP/ATPトランスロケータは,ミトコンドリアの透過性の移行孔には不可欠ではありません
Jason E Kokoszka1, Katrina G Waymire, Shawn E Levy
1Center for Molecular and Mitochondrial Medicine and Genetics, University of California, Irvine, California 92697, USA.
Nature
|January 30, 2004
まとめ
アデニンヌクレオチドトランスロケータ (ANT) は,アポトーシス中のミトコンドリアの透過性移行孔 (mtPTP) の形成に不可欠ではありません. ANTはmtPTPの活性化を調節しますが,その欠如は細胞死亡シグナリングを防ぐことはありません.
科学分野:
- ミトコンドリア生物学 ミトコンドリア生物学
- 細胞死経路について
- バイオケミストリー バイオケミストリー
背景:
- ミトコンドリアの透過性移行孔 (mtPTP) は,アポトーシスの中心にある.
- アデニンヌクレオチドトランスロケータ (ANT) はmtPTPの構成要素であり,ATPとADPを交換する.
- ANTは,細胞死亡の調節に潜在的に関与しています.
研究 の 目的:
- mtPTPの形成と機能におけるANTの役割を調査する.
- mtPTP媒介によるアポトーシスにおいて,ANTが不可欠であるかどうかを判断する.
主な方法:
- ネズミの肝臓におけるANTイソフォームの遺伝的不活性化.
- 孤立したミトコンドリアにおけるmtPTP活性化の分析.
- ヘパトサイトにおける細胞死誘導の評価.
主要な成果:
- ANTが欠けているミトコンドリアは,それでも透性の移行を経験し,シトクロームcを放出することができる.
- ANT欠乏ミトコンドリアのmtPTP活性化にはCa2+の増加が必要でした.
- ANTリガンドが存在しないと,mtPTPを制御できなくなっていた.
- ANTが欠けている肝細胞は,細胞死誘発剤に反応し続けました.
結論:
- ANTはmtPTPの構造的に欠かせない構成要素である.
- ANTは,mtPTPの活性化と機能の制御的な役割を果たします.
- ANTの欠如は,アポプトシスプロセスを廃止しません.
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