細胞死滅細胞死亡経路を調節する分子信号ネットワークの識別
Junichi Hitomi1, Dana E Christofferson, Aylwin Ng
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Cell
|December 27, 2008
まとめ
研究者らは,細胞死経路である死滅を調節する432の遺伝子を特定した. この研究は,死滅とアポトーシスを制御するシグナル伝達ネットワークを定義し,先天性免疫における重要なレギュレータを明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
背景:
- FasLやTNFalphaのような死亡受容体アゴニストは,アポトーシスやネクロプトーシスを誘発する.
- ネクロプトーシス (Necroptosis) は,RIP1キナーゼに依存するプログラム性ネクロシスであり,アポプトシス機構が欠けている細胞で発生する.
研究 の 目的:
- 全ゲノムスクリーンを用いてネクロプトーシスを調節する遺伝子を特定する.
- アポプトーシスとネクロプトーシスの間の分岐を制御するシグナル伝達ネットワークを解明する.
主な方法:
- ネクロプトーシス調節体を特定するための全ゲノム siRNA スクリーン.
- 特定の生物系における遺伝子発現濃縮の分析.
- ネクロプトーシスとアポプトーシスの両方に関与する遺伝子の識別.
主要な成果:
- ネクロプトーシスを調節する432の遺伝子のセットが特定されました.
- RIP1キナーゼのダウンストリームまたはレギュレータとして作用する32の遺伝子が見つかりました.
- 7つの遺伝子は,ネクロプトーシスとアポプトーシスの両方の共通の調節体として特定されました.
- 遺伝子発現の濃縮は,免疫系と神経系で観察されました.
- Bcl-2ファミリーのメンバーであるBmfは,死滅に不可欠であることが判明しました.
結論:
- ネクロプトーシスを調節する包括的な信号ネットワークが定義されています.
- この研究は,死滅とアポトーシスの間のスイッチを制御する分子機構を明らかにしています.
- ネクロプトーシスの調節には,先天的免疫に関連する広範なネットワークが含まれています.
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