関連する実験動画
Updated: May 20, 2026
10:37
Toeprinting Analysis of Translation Initiation Complex Formation on Mammalian mRNAs
Published on: May 10, 2018
トランスレーション型のサイクルは,成熟した40Sリボソームサブユニットの品質管理チェックポイントです
Bethany S Strunk1, Megan N Novak, Crystal L Young
1Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL 33458, USA.
Cell
|July 10, 2012
まとめ
アセンブリ因子 (AFs) は,eIF5BとRli1.1を含むトランスレーション型のサイクルを通じて,成熟するリボソームから異動します. このプロセスは,翻訳開始前にリボソームの忠実性を保証します.
科学分野:
- 分子生物学は分子生物学である.
- リボソームバイオゲネシス
- タンパク質合成 タンパク質合成
背景:
- アセンブリ因子 (AFs) は,リボソームサブユニットの成熟を調節する.
- AFの位移と忠誠度チェックのメカニズムは不明です.
研究 の 目的:
- 40Sリボソーム組立中にAFの移転のプロセスを解明する.
- 翻訳の前にリボソームの忠誠性がどのように確保されているかを理解する.
主な方法:
- リボソームの成熟における翻訳因子eIF5BとRli1の役割を調査した.
- 80Sのような複合体の形成と分解を分析した.
主要な成果:
- リボソームの成熟には,80S型複合体の形成 (eIF5Bによって促進される) と分解 (Rli1によって促進される) のサイクルが伴う.
- AF (Tsr1,Rio2) は,重要なサイトをブロックし,80Sのような複合体での翻訳を防ぐ.
- Rli1-mediated disassemblyは,AF解離後に翻訳を開始することを可能にします.
結論:
- トランスレーション型のサイクルは60Sサブユニット結合とGTPase活性評価を保証します.
- このメカニズムは,早すぎる翻訳開始を防止し,リボソーム質量管理を保証します.
関連する概念動画
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02:07Improving Translational Accuracy
Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
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01:44Termination of Translation
The large ribosomal subunit has several important structures essential to translation. These include the peptidyl transferase center (PTC) - which is the site where the peptide bond is formed - and a large, internal, water-filled tube through which the nascent polypeptide moves. This latter structure is called the Peptide Exit Tunnel, and it begins at the PTC and spans the body of the large ribosomal subunit. During translation, as the nascent polypeptide chain is synthesized, it passes through...
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01:31Translation
Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life