エコライ菌における内生タンパク質S-ニトロシル化:OxyRによる調節
Divya Seth1, Alfred Hausladen, Ya-Juan Wang
1Institute for Transformative Molecular Medicine and Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Case Medical Center, Cleveland, OH 44106, USA.
Science (New York, N.Y.)
|April 28, 2012
まとめ
重要な細胞シグナル伝達プロセスであるタンパク質S-ニトロシレーションは,エシェリキア大腸の無酸素窒素呼吸中に新たに発見されました. 転写因子OxyRは,このプロセスを調節し,既知の有酸素機能を超えて明確な役割を明らかにします.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- タンパク質S-ニトロシル化は,真核細胞の細胞信号伝達に関与する重要な翻訳後の改変である.
- この変異は以前,微生物系では観察されていなかった.
- 転写因子OxyRは,主に有酸素条件下で遺伝子発現を調節することが知られていた.
研究 の 目的:
- 微生物における内生タンパク質S-ニトロシル化の発生と調節を調査する.
- 微生物のS-ニトロシル化における転写因子OxyRの役割を決定する.
- アナーロビック条件下でOxyRによって媒介される独特の転写反応を解明する.
主な方法:
- ニットレートでEscherichia coliの無酸素増殖.
- OxyR遺伝子の削除を含む遺伝子操作.
- タンパク質S-ニトロシル化レベルの分析.
- 有酸素および無酸素条件下でのOxyR調節遺伝子の転写プロファイリング.
主要な成果:
- タンパク質S-ニトロシレーションは,E. coliの窒素による無酸素呼吸中の必須プロセスとして特定されました.
- 転写因子OxyRは,無酸素条件下で内生性S-ニトロシル化を制御する.
- OxyRの削除により,タンパク質S-ニトロシル化が著しく増加しました.
- OxyRのS-ニトロシル化自体は,酸化性レギュロンと分離した,独特の無酸素レギュロンを誘導した.
- アナーロビックレギュロンによる製品は,S-ニトロソチオールに対する保護を与えました.
- OxyRが欠けていた大腸菌は,窒素酸で無酸素成長の障害を示した.
結論:
- OxyRは,E. coliにおけるタンパク質S-ニトロシル化の主調節体として作用し,その機能は無酸素呼吸にまで及ぶ.
- S-ニトロシル化などのOxyRの代替的な翻訳後の改変は,異なる転写プログラムを制御します.
- この研究は,無酸素状態の微生物における細胞信号伝達と適応のための新しい規制メカニズムを明らかにしています.
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