mCpG DNAに対する特定の脱メチラーゼ活性を持つ哺乳類のタンパク質

S K Bhattacharya¹, S Ramchandani, N Cervoni

¹Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada.

Nature

|March 2, 1999

まとめ

科学者たちは新しいDNAデメチラゼ酵素を発見しました. この酵素はメチル化サイトシンをサイトシンに変換し,DNAメチル化と脱メチル化を通じてゲノム機能を調節する上で重要な役割を果たします.

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
ゲノミクスゲノミクスとは

背景:

DNAメチル化パターンは,ゲノム機能を調節するために重要である.
これらのパターンは,酵素によるメチル化および脱メチル化プロセスによって確立および修正されます.
DNA脱メチル化に起因する特定の酵素は,未だに特定されていない.

研究の目的:

DNA脱メチル化に起因する酵素を特定する.
特定されたDNAデメチラーゼの活性と機能を特徴付ける.
開発と疾患におけるDNAメチル化と脱メチル化の研究のための分子基盤を提供すること.

主な方法:

メチル-CpG結合ドメインをコードする哺乳類の補完DNA (cDNA) のクローン化と発現.
デメチラーゼの活性性を評価するためのインビトロ酵素測定法.
cDNAをヒト胚性腎臓細胞に変異させ,プラズミドの脱メチル化活動を観察する.

主要な成果:

メチル-CpG結合ドメインをコードする哺乳類のcDNAが特定されました.
このcDNAは,DNAデメチラゼ活性が有意なタンパク質を発現した.
このタンパク質は, in vitro のプラズミド上で, 細胞塩基を脱メチル化することに成功しました.
デメチラーゼの活性性は,ヒト細胞へのcDNAの翻訳または一時的な転移で確認されました.

結論:

このDNA脱メチラーゼの識別は,分子生物学と発達生物学にとって重要なツールを提供します.
これからの研究により,様々な生物学的プロセスにおけるDNAメチル化と脱メチル化の正確な役割が明らかになる.
この発見は,表遺伝的調節とその細胞機能と発達への影響を理解するための新しい道を開きます.

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