デュアルトランスポーターシステムの競争上の利点
Sagi Levy1, Moshe Kafri, Miri Carmi
1Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
Science (New York, N.Y.)
|December 14, 2011
まとめ
豊富な栄養条件下で高親和の栄養媒体を減らすことは,飢餓への準備時間を短縮しますが,回復を遅らせます. これは,デュアルトランスポーターシステムが,Saccharomyces cerevisiaeのような細胞における栄養素感知と飢餓反応を最適化することを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 栄養素輸送の分子メカニズム
- イースト遺伝学 イースト遺伝学
背景:
- 細胞は,栄養素の吸収を制御するために,異なる親和性を有するトランスポーターを利用します.
- 高親和性トランスポーターは,栄養素が少ない環境では極めて重要ですが,栄養素が豊富な環境では,そのダウンレギュレーションはあまり理解されていません.
研究 の 目的:
- 栄養素の豊富さにおける高親和性トランスポーターの生産減少の役割を調査する.
- 二重トランスポーターシステムの飢餓準備とサッカロマイセス・セレヴィシアの回復への影響を理解する.
主な方法:
- 遺伝子操作により,Saccharomyces cerevisiaeにおける高親和性リン酸塩と亜鉛輸送体の減少した生成を排除する.
- 栄養素の枯渇と回復の段階における成長運動学の分析.
主要な成果:
- 高親近性トランスポーターの生産削減を撤廃することで,飢餓の開始時に成長制限までの時間が短縮されました.
- 飢餓からの回復は,これらの改変された細胞で遅れ,飢餓プログラムの構成的活性化によって救出されたフェノタイプでした.
結論:
- Saccharomyces cerevisiaeのダブルトランスポーターシステムは,飢餓の準備を延ばし,回復を促進する可能性があります.
- これらのシステムは,内部および外部から得られる栄養素の可用性信号を統合することで,栄養素の枯渇感知を最適化する可能性がある.
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