ドロソフィラの遠隔のホックスロシ間のポリコンブ依存の調節コンタクト
Frédéric Bantignies1, Virginie Roure, Itys Comet
1Institut de Génétique Humaine, CNRS UPR 1142, Montpellier, France. frederic.bantignies@igh.cnrs.fr
Cell
|January 19, 2011
まとめ
フルーツフライのホックス遺伝子は,ポリコンブ体内で物理的に相互作用し,遺伝子サイレンスを維持するために重要なプロセスです. この3Dの核組織は,表遺伝的記憶を安定させ,発達に影響を与えます.
科学分野:
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
- エピジェネティクス エピジェネティクス
背景:
- ドロソフィラ・メラノガスターのホックス遺伝子は,前部 (アンテナペディア複合体) と後部 (ビソラックス複合体) のクラスターに分かれています.
- 両方のホックス遺伝子クラスターは,ポリコンブ群 (PcG) タンパク質によって表遺伝的に抑制されています.
研究 の 目的:
- 原子核内のホックス遺伝子クラスターの空間的組織と相互作用を調査する.
- これらの相互作用を媒介するPcGタンパク質の役割と,遺伝子サイレンシングへの影響を決定する.
主な方法:
- 顕微鏡技術を使用して,ドロソフィラ菌の組織内のPcG体内のホックス遺伝子コロカライゼーションを観察しました.
- これらの相互作用の発達とPcG依存性の性質を調査した.
- 他のPcG標的遺伝子を含む遺伝子相互作用ネットワークを調べた.
- ホックス遺伝子サイレンシングとホメオティック現象型に対する突然変異の影響を分析した.
主要な成果:
- 2つのホックス複合体の遺伝子は,コアプレッション中に核PcG体内にコロカライズされます.
- このコロカライゼーションは発達期に強まり,PcGタンパク質に依存しています.
- ホックス遺伝子の接触は,種を超えて保存され,より広範なPcG標的遺伝子のネットワークに統合されます.
- あるホックス・ロクスの突然変異は,他のホックス・ロクスの突然変異を抑制し,ホメオティック現象型を悪化させる.
結論:
- 核内のポリコンブ標的遺伝子の3次元の組織は,安定した表遺伝子遺伝子のサイレンシングに不可欠です.
- PcGタンパク質による核構造は,発達の遺伝子発現パターンを維持する上で重要な役割を果たします.
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