クラミドモナスの核のNAC2ロカスにおける突然変異は,特にクロロプラストのpsbDトランスクリプトの安定性に影響を及ぼし,PS IIのポリペプチドD2をコードするPS IIのポリペプチドD2をコードする
M R Kuchka1, M Goldschmidt-Clermont, J van Dillewijn
1Department of Plant, University of Geneva, Switzerland.
Cell
|September 8, 1989
まとめ
NAC2遺伝子製品は,クロロプラストD2タンパク質 (psbD) のトランスクリプトをクラミドモナスの再硬化に安定させる. NAC2がなければ,psbD mRNAは分解され,不安定な光系II (PS II) 複合体となる.
科学分野:
- 分子生物学は分子生物学である.
- 光合成研究 研究 光合成研究
- 植物遺伝学 植物遺伝学
背景:
- クロロプラストD2タンパク質は,光システムII (PSII) の機能に不可欠です.
- トランスクリプトの安定性は,適切なタンパク質合成と複合体の組み立てに不可欠です.
- 核コード化された因子は,クロロプラストの遺伝子発現をクロロドモナス・リアンハーディに調節することができます.
研究 の 目的:
- クロロプラストの遺伝子発現を調節するNAC2遺伝子の機能を調査する.
- D2タンパク質をコードするpsbDトランスクリプトの安定性におけるNAC2の役割を決定する.
- 光系IIの複合体の構成と安定性に対するNAC2の影響を理解する.
主な方法:
- 野生型およびnac2変異株におけるpsbDトランスクリプトレベルの分析.
- nac2変異体におけるPSIIタンパク質の蓄積と複合体の安定性の評価.
- psaAのスプライシングとNAC2の機能に影響する二重変異体におけるスプライシング中間物質の調査.
主要な成果:
- nac2-26変異は,psbDトランスクリプトの蓄積を防ぐ.
- PS II複合体は不安定であり,主要なPS IIポリペプチドは,nac2-26変異体で分解される.
- psbD配列を含むスプライシング中間物質は,NAC2とpsaAスプライシングが欠けているダブルミュータントで分解されます.
- NAC2遺伝子製品は,特にpsbDトランスクリプトの半減期を制御する.
結論:
- NAC2遺伝子は,psbD mRNAの安定性にとって不可欠な核因子をコードする.
- NAC2媒介のpsbDトランスクリプトの安定性は,光系II複合体の完全性にとって重要である.
- NAC2の機能はpsbDのトランスクリプト処理に特異的であり,他のPS IIコンポーネントやpsaAスプライシングに大きな影響を与えない.
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