トランポゾンから抽出されたTnpB同型は,RNA誘導の転写因子である
Tanner Wiegand1, Florian T Hoffmann1, Matt W G Walker2
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
Nature
|June 26, 2024
まとめ
トランポゾンでコードされたTnpBタンパク質は,プログラム可能な転写因子として作用するTnpBのような核酸死抑制剤 (TldRs) として再利用された. バクテリオファージはTldRを利用して宿主の鞭状組織を修正し,運動性と免疫に影響を与えます.
科学分野:
- 分子生物学
- 遺伝学
- 進化生物学
背景:
- トランポゾンでコードされたTnpBおよびIscB遺伝子は,トランポゾン移動に関与するRNA誘導DNA核酸である.
- これらの遺伝子は繰り返し家畜化され,Cas9やCas12のようなCRISPR関連ニュクレアスが生まれました.
- 調査された仮説は,TnpB核酸がCRISPR-Cas適応免疫以外の機能に再利用されているかどうかである.
研究 の 目的:
- 適応免疫における役割を超えたTnpB核酸の新しい機能を調査する.
- TnpBから派生した新しい種類のタンパク質を特定し,特徴づけること.
- タンパク質の進化の起源と仕組みを理解する
主な方法:
- 系統遺伝分析
- 構造的予測
- 比較ゲノミクス
- 機能検査
主要な成果:
- プログラム可能な転写因子,TnpBのような核酸死抑制剤 (TldRs) の複数の独立した創生イベントの発見.
- TldRはガイドRNAを使用して特定のゲノムプロモーター領域を標的とし,強力な遺伝子抑制につながります.
- バクテリオファージはTldRを利用して宿主の鞭状組織を変化させ,その運動性,ファージの感受性,宿主の免疫に影響を与えます.
結論:
- TnpB核酵素は,多様なRNA誘導転写因子を生成するために複数回抽出されています.
- TldRは,遺伝子調節を理解する上で重要な意味を持つプログラム可能な遺伝子抑制剤の新種である.
- TldRsによる宿主鞭状遺伝子の細菌による操作は,進化の革新と王国間の相互作用を強調する.
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