騒音によって引き起こされる信号伝導の強化は,電圧に依存するイオンチャネルを介して発生します
1Division of Computer Research and Technology, National Institutes of Health, Bethesda, Maryland 20892-0580, USA.
Nature
|November 23, 1995
まとめ
騒音は,生物学的信号検出を驚くほど強化することができます. この研究は,単純なイオンチャネルにおけるストキャスティック共振を実証し,騒音が細胞下レベルでの小さな信号をどのように増幅するかを示しています.
科学分野:
- バイオフィジックス 生物物理学
- システム生物学 システム生物学
- バイオケミストリー バイオケミストリー
背景:
- 信号伝達システムは,信頼性の高い情報伝送のために,通常,ノイズを最小限に抑えることに依存しています.
- 非線形システムは,ノイズを利用してパフォーマンスを向上させることができ,これはストキャスティック共鳴として知られる現象である.
- ストキャスティック共鳴は複雑な生物系で観察されているが,細胞下レベルでの発生は不明である.
研究 の 目的:
- サブセルラーレベルでストキャスティック共鳴の可能性を調査する.
- イオンチャネルのような単純な生物系がノイズ強化信号伝導を示すことができるかどうかを判断する.
- 騒々しい生物環境における小さな信号の増幅におけるストキャスティック共振の役割を調査する.
主な方法:
- ペプチドであるアラメチシンによって形成された電圧依存イオンチャネルのシステムを利用した.
- イオンチャネルシステムに適用された外部ノイズ.
- 異なる騒音レベルに対応して,測定された信号伝導と出力信号対騒音比.
主要な成果:
- アラメチシンイオンチャネルシステムにおけるストキャスティック共振の観測.
- 外部ノイズが導入されたとき,信号伝導の百倍の増加が実証されました.
- 出力信号対ノイズ比の同時増加を示し,信号検出の強化を示した.
結論:
- ストキャスティック共鳴は,生物学的システムにおけるサブセルラーレベルで発生することがあります.
- アラメチシンイオンチャネルシステムは,ストキャスティック共鳴を示す最も単純な生物学的システムです.
- 騒音は,分子レベルでさえも,生物学的システムにおける信号検出と増幅を強化する上で重要な役割を果たすことができます.
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