標的配列は,DNAメチルトランスフェラーゼを哺乳類の核におけるDNA複製の部位に誘導する

H Leonhardt¹, A W Page, H U Weier

¹Department of Anatomy and Cellular Biology, Harvard Medical School, Boston, Massachusetts 02115.

Cell

|November 27, 1992

まとめ

DNAメチルトランスフェラーゼ (MTase) は,DNA合成中の複製フォークを標的にします. 新しいN端末配列が,この細胞周期特異的な局所化を指示し,ゲノムメチル化パターンの維持に不可欠です.

科学分野:

分子生物学は分子生物学である.
エピジェネティクスエピジェネティクス
細胞生物学細胞生物学

背景:

ゲノムメチル化パターンは,哺乳類のゲノム調節に極めて重要です.
複製後のメチル化は,DNA複製中のこれらのパターンの継承を保証する.
このプロセスにはDNAメチルトランスフェラーゼ (MTase) の活性が不可欠である.

研究の目的:

DNAメチルトランスフェラーゼ (MTase) の細胞サイクル局在性を調査する.
メタゼが複製焦点と結合するメカニズムを特定する.
DNA MTase内の新しいターゲティング配列を特徴付けるために.

主な方法:

免疫光顕微鏡で,細胞サイクル中のMTase局所化を視覚化します.
DNA MTase-β-ギャラクソシダゼ融合タンパク質の分析.
サイト・ディレクテッド・ミュータゲネシスで,推定標的配列を削除または移転する.

主要な成果:

DNA MTaseはS相の間に複製焦点に局所化し,S相以外の細胞で拡散した核プラズマ分布を示します.
DNA MTaseのN端近くにある新しい標的配列は,複製焦点との関連を媒介する.
このターゲティング配列は酵素活性とは独立しており,細胞周期に依存する局所化を異質タンパク質に与えます.

結論:

特定のN末端配列は,S相においてDNAMTASEを複製部位に誘導する.
この局所化メカニズムは,DNA複製中に表遺伝的忠誠性を維持するために極めて重要です.
特定された標的配列は,細胞サイクルに依存した方法でタンパク質の局所化を研究するための新しいツールを提供します.

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