GCN4 mRNAの翻訳活性化とポリペプチド鎖開始率の低下との結合
D Tzamarias1, I Roussou, G Thireos
1Foundation of Research and Technology, Institute for Molecular Biology and Biotechnology, Heraklio, Crete, Greece.
Cell
|June 16, 1989
まとめ
研究者らは,GCN2タンパク質キナーゼとは独立して,GCN4タンパク質合成の迅速かつ一時的な上昇を引き起こす条件を発見した. このGCN4 mRNAの翻訳的活性化は,全体的なタンパク質合成率の低下と関連しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子発現の規制について
- タンパク質合成 タンパク質合成
背景:
- GCN4 mRNAの翻訳活性化は,通常,GCN2タンパク質キナーゼまたは欠陥GCD1機能によって媒介されます.
- このプロセスは,5'上流のオープン読み取りフレームを翻訳した後,タンパク質をコードするAUGでリボソームのイニシアチブを伴う.
研究 の 目的:
- GCN4タンパク質合成の一時的な増加につながる条件を特定する.
- GCN4トランスレーションとグローバルなタンパク質合成速度との関係を調査する.
- 翻訳開始時に影響を受ける特定のメカニズムを解明する.
主な方法:
- 暫定的なGCN4タンパク質合成を引き起こす条件を調査した.
- この活性化におけるGCN2タンパク質キナーゼの役割を分析した.
- 細胞全体のタンパク質合成率への影響を調べました.
- 43S 前始動複合体の形成を評価した.
主要な成果:
- GCN2.2とは独立して,GCN4タンパク質合成の劇的で一時的な増加の条件を特定した.
- この活性化は,グローバルなタンパク質合成の減少と一致していることが観察されました.
- gcd1株とGCN2を過剰発現する株で低タンパク質合成率を発見した.
- 影響を受けたプロセスは,43Sの前始動複合体の形成であることが決定されました.
結論:
- GCN2.2とは独立して,一時的なGCN4 mRNAの翻訳活性化のための新しいメカニズムが存在する.
- この活性化は,全体的なタンパク質合成の減少と結びついています.
- 43S前始動複合体の形成は,グローバルとGCN4固有の翻訳を結びつける重要な規制ポイントです.
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