S. cerevisiaeの糸状成長シグナル伝達経路におけるMAPK Kss1に対する抑制および活性化機能

J G Cook¹, L Bardwell, J Thorner

¹Department of Molecular and Cell Biology, University of California, Berkeley 94720-3202, USA.

Nature

|November 18, 1997

まとめ

ミトゲン活性化タンパク質キナーゼ (MAPK) のカスケードは,細胞の反応を調節する. イーストでは,Ste7は侵入的成長のためにKss1を活性化し,Kss1を明らかにします.

科学分野:

細胞の信号伝達経路は,
分子生物学は分子生物学である.
イースト遺伝学イースト遺伝学

背景:

ミトゲン活性化タンパク質キナーゼ (MAPK) のカスケードは,外部刺激や環境変化に対する細胞の反応に不可欠です.
Saccharomyces cerevisiaeでは,MAPKキナーゼ (MAPKK) Ste7が交配と侵襲的な成長経路に関与しています.
MAPKの標的Kss1とFus3の侵入性増殖における特定の役割は,以前は不明でした.

研究の目的:

"Saccharomyces cerevisiae"の侵入性成長経路におけるSte7とそのMAPK標的の役割を解明する.
Ste7が,前述の仮説通り,MAPK以外のターゲットに作用するかどうかを判断する.
侵襲的な成長におけるKss1の機能を特徴づける.

主な方法:

Saccharomyces cerevisiae.の遺伝子解析について
MAPKの信号伝達経路を調査する.
野生型とMAPK欠乏酵母菌株を比較する.

主要な成果:

Kss1は,侵入性成長応答におけるSte7の主要なMAPK標的として特定されました.
不活性なKss1は,侵襲的な成長の負の調節剤として作用する.
Ste7の活性化は,Kss1を阻害者から活性化器に切り替え,負の調節を緩和します.

結論:

MAPK Kss1は侵入的成長において重要な役割を果たし,活性化されていない状態でも機能します.
Kss1に対するSte7の作用は,糸状の成長を促進するために重要である.
MAPKに依存する経路とMAPKに依存しない経路の両方が,窒素飢餓とRas刺激された有糸体の成長に貢献します.

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