ラパミシン感受性経路によるIGF-II mRNAの成長依存翻訳
F C Nielsen1, L Ostergaard, J Nielsen
1Department of Clinical Biochemistry, Rigshospitalet, Copenhagen O, Denmark.
Nature
|September 28, 1995
まとめ
人間のIGF-II遺伝子は,2つの主要なmRNAタイプを生成します. マイナーなmRNAは継続的にprepro-IGF-IIを作り,メジャーなmRNAは特定のキナーゼ経路によって翻訳的に調節される.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
背景:
- インスリンのような成長因子 (IGF) -IIは胎児の成長に不可欠です.
- 人間のIGF-II遺伝子は,異なる5'未翻訳領域 (5'UTRs) を含む複数のmRNAトランスクリプトを生成する.
- 以前は,4.8kbのmRNAがpre-pro-IGF-II合成のために特定され,6.0kbのmRNAが翻訳されず,100Sリボ核タンパク質粒子に保存されていることが判明しました.
研究 の 目的:
- 6.0kbのIGF-II mRNAの翻訳調節を調査する.
- 6.0kbのIGF-II mRNAの動員と翻訳に関与するシグナル伝達経路を解明する.
主な方法:
- 分散した指数関数的に成長する細胞の細胞培養.
- ラパミシンとアニソミシンによる治療は,翻訳調節を研究するために.
- mRNAの動員と翻訳の分析.
主要な成果:
- 6.0kbのIGF-II mRNAは,指数関数的に成長する細胞で選択的に動員され,翻訳されます.
- ラパミシンは6.0kbmRNAの翻訳を阻害し,アニソミシンはそれを模倣する.
- これは,p70S6k/85S6kキナーゼシグナル伝達経路による規制を示唆しています.
結論:
- 4.8kbのIGF-II mRNAは,構成的なprepro-IGF-II生産を保証しています.
- 6.0kbのIGF-II mRNAは,転写後の調節された種を表しています.
- p70S6k/85S6k経路は,主要なIGF-II mRNAトランスクリプトの翻訳を制御する.
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