ハエのMCM複合体の進化は,BLMヘリケースを阻害することによって,メオティッククロスオーバーを促進します
Kathryn P Kohl1, Corbin D Jones, Jeff Sekelsky
1Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA.
まとめ
ハエでは,ミニクロモソーム維持 (MCM) タンパク質がMsh4-Msh5複合体を置き換えて,メオティッククロスオーバーの生成を保証しました. このMCM複合体は,クロスオーバーを容易にするために進化し,Msh4-Msh5.5の損失を克服しました.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- ユカリオットのメイオティッククロスオーバー形成には,しばしばMsh4-Msh5ヘテロダイマーが抗クロスオーバーヘリカーゼを阻害する.
- Msh4およびMsh5タンパク質は,DrosophilaやGlossina.のようなハエには存在しない.
研究 の 目的:
- ミエオティッククロスオーバー生成のために,ドロソフィラのMsh4-Msh5ヘテロダイマーを機能的に置き換えるタンパク質を特定する.
- これらの置換タンパク質の進化的起源と機能を調査する.
主な方法:
- ドロソフィラの変異体の基因解析で,鍵となる遺伝子 (rec, mei-217, mei-218) を調べました.
- タンパク質複合体を特定するための生化学相互作用の研究.
- MCMタンパク質の進化史を追跡するための比較ゲノミクス.
主要な成果:
- REC (MCM8 ortholog) と新しいタンパク質MEI-217/MEI-218を含むミニクロモソーム維持 (MCM) タンパク質の複合体が特定されました.
- RECはハエの陽性選択により進化し,メタゾーン特異のMCMタンパク質であるMEI-217/MEI-218と相互作用する.
- rec,mei-217,または mei-218の変異により,メオティッククロスオーバーが減少したが,これはブルーム症候群ヘリケーズ (BLM) を除去することによって救われた.
結論:
- ミニクロモソームメンテナンス (MCM) タンパク質は,ハエのMsh4-Msh5のメオティック・プロ・クロスオーバー機能を代替する新しい複合体を形成するために再利用されました.
- このMCM複合体は,Msh4-Msh5.5が存在しない場合,メオティッククロスオーバーを調節する上で重要な役割を果たします.
関連する概念動画
M-Cdk Drives Transition Into Mitosis
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M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
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Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
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