MyoD DNA結合ドメインには,筋肉特異的な遺伝子活性化のための認識コードが含まれています
R L Davis1, P F Cheng, A B Lassar
1Department of Genetics, Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|March 9, 1990
まとめ
MyoDの基本領域は,DNA結合と筋肉遺伝子の活性化に不可欠です. この領域を交換すると,DNA結合能力であっても,筋肉プログラムの活性化が妨げられます.
科学分野:
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学について
- 遺伝学 遺伝学とは
背景:
- ミオゲン決定遺伝子のMyoDは,筋肉の発達に重要な役割を果たしています.
- MyoDの特定の60アミノ酸ドメインは,その機能に不可欠であることが知られている.
研究 の 目的:
- MyoDドメイン内の特定の領域を特定し,配列特異のDNA結合とミオゲン変換を担当します.
- MyoDの機能におけるヘリックス・ループ・ヘリックス (HLH) モチーフと上流基本領域の役割を調査する.
主な方法:
- サイト指向型変異は,MyoD遺伝子の特定の領域を交換するために使用されました.
- 配列特異的結合を評価するために,インビトロDNA結合アッセイが行われました.
- C3H10T1/2細胞を用いたトランスフェクションアッセイは,ミオジェニック変換と筋肉特異的な遺伝子活性化を評価するために実施されました.
主要な成果:
- HLHモチーフの上流にある非常に基本的な領域は,MyoDの in vitro DNA結合に不可欠です.
- ヘリックス1,ヘリックス2,またはMyoDのループをDrosophila T4のアカイテ-スキュートタンパク質からの類似の配列に置き換えると,DNA結合または筋肉遺伝子活性化に影響を与えませんでした.
- MyoD基本領域をE12またはT4アカエテ-スキュートタンパク質の配列に置き換えることで,DNA結合が認められたが,筋肉特有の遺伝子活性化は廃止された.
結論:
- MyoDの基本領域には,筋肉特異遺伝子の活性化に不可欠な認識コードが含まれています.
- シーケンス固有のDNA結合だけでは,筋肉開発プログラムを起動するには不十分です; 基本的な領域の特定のシーケンスが必要です.
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