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Updated: May 10, 2026
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Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling
Published on: October 28, 2014
誘発因子eIF5B/IF2のGTPaseと,リボソーム親和性を低下させる突然変異によるトランスレーション活動の解離
Byung-Sik Shin1, David Maag, Antonina Roll-Mecak
1Laboratory of Gene Regulation and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Cell
|January 1, 2003
まとめ
翻訳開始因子eIF5Bの変異は,GTPの水解を阻害し,一般的な翻訳に影響するが,サブユニット結合には影響しない. 抑制剤はリボソームの親和性を減少させることで翻訳を回復し,eIF5B GTPの水解が規制チェックポイントであることを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
- 遺伝学 遺伝学とは
背景:
- 翻訳開始因子eIF5B (IF2とも呼ばれる) は,タンパク質合成中にリボソームサブユニットの結合に不可欠なGTPaseである.
- そのGTP結合領域には,GTP酵素活性に不可欠なSwitch Iのような保存された元素が含まれています.
研究 の 目的:
- 翻訳開始におけるeIF5BのGTPase活動の役割を調査する.
- GTPの水解がリボソームサブユニット結合に不可欠であるか,または規制機能を持つかどうかを判断する.
主な方法:
- eIF5B.におけるSwitch I要素のサイト指向型変異.
- GTP水解,リボソームサブユニット結合,および一般的なトランスレーションに関するアッセイ.
- 内遺伝抑制剤の分析とリボソーム結合とAUG選択に対するその影響.
主要な成果:
- スイッチIの変異は,GTPの水解と一般的な翻訳を阻害したが,サブユニットの結合機能を保持した.
- イントラジェニック抑制剤は,GTPaseの活性を取り戻すことなく,一般的な翻訳を復元しました.
- サプレッサー変異により,リボソームの親和性が低下し,AUGスタートコドンの漏れ性スキャンが増加しました.
結論:
- eIF5BによるGTPの水解は,リボソームサブユニット結合に不可欠ではないが,翻訳の開始に規制的な役割を果たしている可能性が高い.
- eIF5B GTP水解は,80Sリボソーム組成のチェックポイントとして作用し,潜在的にMet-tRNAの結合を安定させ,Met-tRNAを結合させる.
関連する概念動画
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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
02:33Initiation of Translation
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs.
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...