代替的にスプライスされたTCR mRNAは,読み取りフレームの破壊によって誘発されます
Jun Wang1, John I Hamilton, Mark S Carter
1Department of Immunology, The University of Texas M. D. Anderson Cancer Center, Box 180, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
Science (New York, N.Y.)
|July 6, 2002
まとめ
遺伝子の突然変異を早期に終結させると,欠陥のあるタンパク質が生まれます. 新しい研究では,これらの変異を回避する代替のスプライシングメカニズムが明らかにされ,遺伝子発現制御に関する新しい視点が提供されています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 免疫学 免疫学とは
背景:
- ナンセンスコドンは早めにタンパク質翻訳を終了させ,潜在的に有害な断片化されたタンパク質につながります.
- T細胞受容体β (TCRbeta) 遺伝子は,リンパ球発達の過程で,しばしばインフレームナンセンスコードンを獲得する.
研究 の 目的:
- TCRbeta遺伝子が高周波ナンセンスコードンを処理するメカニズムを調査する.
- 翻訳エラーに対応して,代替的にスプライスされたトランスクリプトがどのように調整されるかを理解する.
主な方法:
- リンパ球における遺伝子発現の分析.
- 代替スプライスされたトランスクリプト (アルト-mRNAs) の識別と特徴付け.
- 転送RNA (tRNA) と読み取りフレームの整合性が,アルトmRNAレベルを調節する上で果たす役割を調査する.
主要な成果:
- TCRbeta遺伝子は,ナンセンスコドンをスキップするアルトmRNAを生成する.
- このAlt-mRNAは,転送RNAに依存したスキャンメカニズムによって上位調節されます.
- このメカニズムは,遺伝子の読み取り枠を乱す突然変異に特異的に反応する.
結論:
- トランスレーション信号は,核内の代替的にスプライスされたmRNAの生成を調節することができます.
- この発見は,真核生物の遺伝子発現制御に関する現在の理解を再構築する可能性があります.
- トランスレーションフィデリティに関連した新しいRNAスプライシング調節経路を特定しました.
関連する概念動画
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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.
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Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
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