BRCA1腫瘍抑制は,ヘテロクロマチン媒介のサイレンシングによって起こります
Quan Zhu1, Gerald M Pao, Alexis M Huynh
1Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California 92037, USA.
Nature
|September 9, 2011
まとめ
BRCA1 (乳がん遺伝子1) 腫瘍抑制剤の喪失は,衛星DNAを抑制し,ゲノム不安定化につながります. BRCA1はヒストンH2Aの汎用化によってヘテロクロマチン構造を維持しており,これは癌の予防に極めて重要です.
科学分野:
- 遺伝学 遺伝学とは
- エピジェネティクス エピジェネティクス
- 癌生物学 癌生物学について
背景:
- BRCA1腫瘍抑制遺伝子の変異は,遺伝性乳がんおよび卵巣がんと関連しています.
- BRCA1の喪失が腫瘍形成に寄与する正確なメカニズムは,完全に理解されていません.
- ゲノム整合性を維持するBRCA1の役割は,その腫瘍抑制機能にとって重要です.
研究 の 目的:
- 衛星DNA転写の調節におけるBRCA1の機能的役割を調査する.
- BRCA1の腫瘍抑制活性に基づく分子メカニズムを解明する.
- BRCA1媒介によるヘテロクロマチンの維持が,BRCA1欠乏性がんにおいて関連性があるかどうかを判断する.
主な方法:
- Brca1欠乏症のマウスモデルを使用した.
- 複合的に繰り返される衛星DNAの転写変化を分析した.
- 衛星の繰り返し領域で評価されたヒストンH2Aの普遍性.
- ヒストンH2A-ユビキチン融合タンパク質のエクトピック発現を用いた.
- ヒトのBRCA1欠乏性乳がんのサンプルにおける衛星DNA抑制抑制を調査した.
主要な成果:
- ネズミのBrca1の喪失は,衛星DNAの転写性抑制を解除することにつながった.
- Brca1の欠乏は,ゲノム凝縮の減少と,衛星の繰り返しでヒストンH2Aの汎用性の喪失につながった.
- BRCA1は衛星DNAに直接結合し,H2Aのユビキチテレーションを vivoで媒介する.
- H2A-ubiquitinの子宮外発現は,BRCA1喪失の影響を逆転させました.
- 衛星DNA減圧は,ヒトのBRCA1欠乏性乳がんにおいて観察された.
- エクトピック衛星DNA発現は,ゲノム不安定性を含む,フェノコピーされたBRCA1喪失効果.
結論:
- BRCA1は,衛星DNAの繰り返しでヒストンH2Aの汎用化によってヘテロクロマチン構造を維持するために不可欠です.
- 衛星DNAの調節不良は,BRCA1欠乏がんにおいて観察されるゲノム不安定に寄与する.
- 全球ヘテロクロマチンの整合性におけるBRCA1の役割は,その腫瘍抑制機能の重要な側面である.
さらに関連する動画
08:15gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair
Published on: October 6, 2014
09:24Silencing of BRCA2 to Identify Novel BRCA2-regulated Biological Functions in Cultured Human Cells
Published on: August 12, 2015
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