バクテリオファージT4遺伝子6060のコーディングギャップのリボソームバイパスには新生ペプチドが必要である
R B Weiss1, W M Huang, D M Dunn
1Howard Hughes Medical Institute, University of Utah, Salt Lake City, Utah.
Cell
|July 13, 1990
まとめ
バクテリオファージT4遺伝子60 mRNAには,リボソームがバイパスできる未翻訳領域があります. この翻訳バイパスは,特定のポリペプチドを合成するために不可欠であり,新生ペプチド,複製,および茎ループ構造を必要とします.
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
- ウイルス学 ウイルス学 ウイルス学
背景:
- バクテリオファージT4遺伝子60はDNAトポイソメラーゼをコードする.
- そのmRNAには,コード配列内の50核性otideの未翻訳領域が含まれています.
- この領域の翻訳バイパスは,18 kDaのポリペプチドを合成するために提案されています.
研究 の 目的:
- バクテリオファージT4遺伝子60におけるトランスレーションバイパスメカニズムを調査する.
- リボソームバイパスに必要な重要な配列と構造要素を特定する.
主な方法:
- 遺伝子60-lacZ融合における変異 (削除,挿入,置換) の分析.
- E. coli.における60-lacZ融合遺伝子改変の発現
- リボソームバイパス効率の評価.
主要な成果:
- 遺伝子60-lacZ融合の翻訳されていない領域のリボソームバイパスは,高効率 (ほぼ100%) で発生します.
- 高レベルバイパスの重要な要素には,シス作用の新生ペプチド,ギャップ・ボーダーでの短い重複,およびストップ・コドンを持つ5'交差点の茎ループが含まれます.
結論:
- 内部mRNA領域の翻訳バイパスを制御する重要なcis作用要素を特定しました.
- スプリットコーディングセグメントポリペプチドの合成に関する洞察を提供します.
- 遺伝子発現におけるプログラムされたリボソームのフレームシフトまたはバイパスのためのメカニズムを明らかにします.
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