免疫グロブリンmu遺伝子の活性転写状態の安定的な伝播には,継続的な強化機能機能が必要である
1Department of Microbiology and Immunology, University of California, San Francisco 94143.
Cell
|November 18, 1988
まとめ
免疫グロブリン重鎖遺伝子発現には,初期活性化と持続的な転写の両方のために強化剤が必要です. 増強剤を削除すると遺伝子発現が停止し,記憶機能がないことを示します.
科学分野:
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
背景:
- エンハンサー配列は,遺伝子発現を制御する重要な規制要素である.
- 免疫グロブリン・ム重鎖遺伝子の発現は,強化剤によって調節される.
- 細胞分裂に際してトランスクリプション状態がどのように維持されるかを理解することは極めて重要です.
研究 の 目的:
- 強化成分が免疫グロブリンム重鎖遺伝子に転写活動の"記憶"を与えるかどうかを調査する.
- 増強剤の削除後,子細胞でmu遺伝子の活性転写状態が維持できるかどうかを決定する.
- 遺伝子発現の確立と維持の両方における強化剤の役割を評価する.
主な方法:
- 増強剤を含む改変したム遺伝子が,B前細胞に安定して導入される.
- D-to-J 再結合の誘導により,強化剤の配列が削除されます.
- 強化剤の削除前と後のmu遺伝子転写のモニタリング.
- mu遺伝子のDNAメチル化状態の分析.
主要な成果:
- Mu遺伝子転写は,pre-B細胞への安定した導入時に開始されました.
- D-to-J結合経由での増強剤の後の削除は,再現可能で静止されたmu遺伝子発現を引き起こした.
- 転写不活性化は,増強剤の削除前に遺伝子が低メチル化されているにもかかわらず発生しました.
- 増強剤は,mu遺伝子発現を維持するために必要である.
結論:
- 増強剤は,免疫グロブリンム重鎖遺伝子に転写活動の"記憶"を与えない.
- 増強剤は,ミュー遺伝子発現の初期確立と継続的な維持の両方にとって不可欠です.
- トランスクリプションサイレンシングは,DNAメチル化状態に関係なく,増強剤の削除時に発生します.
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