マッピング ビトラクスの複合体内のポリコンブ抑制ドメインは, in vivo フォーマルデヒドとクロスリンクされたクロマチンを用いてマッピングしています
1Zentrum für Molekulare Biologie, Universität Heidelberg, Federal Republic of Germany.
Cell
|December 17, 1993
まとめ
ポリコンブ群 (Pc-G) タンパク質は,ドロソフィラの発達遺伝子の安定した抑制を維持する. Pc-Gタンパク質は,ビソラックス複合体 (BX-C) 内の抑圧された遺伝子の大きな調節領域に結合します.
科学分野:
- 発達生物学 発達生物学とは
- エピジェネティクス エピジェネティクス
- クロマチンの生物学
背景:
- ポリコンブ群 (Pc-G) タンパク質は,発達中の遺伝性遺伝子抑制に不可欠です.
- Pc-Gタンパク質は,ヘテロクロマチンの形成と高階クロマチンの構造に関与しています.
- ビソラックス複合体 (BX-C) のようなホメオティック遺伝子は,Pc-Gがターゲットとする重要な発達調節因子です.
研究 の 目的:
- Drosophila bithorax複合体 (BX-C) 内のポリコンブ (Pc) タンパク質の分布をマッピングする.
- 染色体レベルでのPcタンパク質結合と遺伝子抑制の関係を調査する.
主な方法:
- 生命体内のフォーマルデヒドクロスリンク技術の開発.
- Pcと相互作用するクロマチンの部位を,抗-Pc抗体による免疫プレシピテーションで濃縮する.
- ドロソフィラ菌の組織培養細胞におけるPcタンパク質分布の分析.
主要な成果:
- Pcタンパク質は,抑制されたBX-C遺伝子の広大な規制領域を定量的にカバーしています.
- これらの細胞で活性であることが判明したAbdominal-B遺伝子は,結合したPcタンパク質のない領域を示しています.
- Pc結合と遺伝子サイレンシングの間の直接的な相関を示しています.
結論:
- Pc-Gタンパク質は,発達遺伝子の抑制状態を維持する上で重要な役割を果たします.
- Pcタンパク質の分布は,BX-C内の静止された遺伝子の規制領域に正確にマッピングされています.
- この研究は,PCG媒介によるクロマチンのレベルの遺伝子調節の分子証拠を提供します.
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