酵母タンパク質の翻訳の速度を制限するステップ
Premal Shah1, Yang Ding, Malwina Niemczyk
1Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Cell
|June 25, 2013
まとめ
この研究は酵母翻訳をモデル化し,タンパク質の生産は通常,リボソームの可用性によって制限されていることを明らかにしています. ストレス下では,翻訳開始または延長を減らすことで,タンパク質の収量を改善することができます.
科学分野:
- 分子生物学は分子生物学である.
- コンピュータ生物学 コンピュータ生物学
- システム生物学 システム生物学
背景:
- ディープシーケンシングは,メッセンジャーRNA (mRNA) のリボソーム占有量の詳細なデータを提供します.
- 翻訳を理解することは,細胞の機能とタンパク質の生産に不可欠です.
研究 の 目的:
- 酵母における翻訳の計算モデルをパラメータ化するために.
- トランスゲンと内生遺伝子のタンパク質収量に影響を与える要因を決定する.
- Saccharomyces cerevisiae遺伝子の翻訳開始率を推論するために.
主な方法:
- リボソーム占有率のディープシーケンシングデータを活用する.
- リボソーム,トランスファーRNA (tRNA),mRNAを追跡する計算モデルを開発.
- タンパク質の収量に影響を与えるパラメータレジームを分析し,開始率を推論する.
主要な成果:
- 迅速な初期化または高コドンバイアスがタンパク質の収穫量を増加させる条件を特定した.
- 推測された酵母遺伝子のイニシアーション率は5'mRNAの折りたたみエネルギーと相関し,数量順に変化します.
- リボソーム密度が減少する5'-to-3'のランプを確認し,それを短い遺伝子の急速なイニシアチブと結び付けました.
結論:
- 健康な酵母におけるタンパク質の生産は,通常,自由リボソームの可用性によって制限されます.
- ストレスのとき,タンパク質の生成は,開始または延長速度を調節することによって強化することができます.
- この研究は,酵母における翻訳とタンパク質合成の調節に関する洞察を提供します.
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