長い神経遺伝子は,ニューラル幹細胞/原始細胞における再発性DNA断裂クラスタを宿している
Pei-Chi Wei1, Amelia N Chang1, Jennifer Kao1
1Program in Cellular and Molecular Medicine, Boston Children's Hospital, Howard Hughes Medical Institute, Boston, MA 02115, USA; Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA.
Cell
|February 13, 2016
まとめ
DNAの二重鎖の断裂は 神経の発達に不可欠です この研究では,神経幹細胞に再発性DSBがある特定のゲノム領域を特定し,神経機能と障害に関連した脆弱な部位を明らかにします.
科学分野:
- ゲノミクス
- 神経科学
- 分子生物学
背景:
- DNA二重鎖断裂 (DSB) の非同類末端結合 (NHEJ) の修復は,神経の発達に不可欠である.
- 脳細胞の体内のゲノム変異は,DSBの中間物質を含む可能性があります.
研究 の 目的:
- 主要な神経幹細胞/原始細胞 (NSPC) で再発性DSBを持つゲノム領域を,偏見のない高通量アプローチを使用して特定する.
- これらの DSB サイトのゲノム特性と機能的影響を特徴づける.
主な方法:
- NSPCで再発するDSBクラスター (RDC) を検出するために,偏りのない高通量メソッドを使用しました.
- アフィジコリンを使った 軽度の複製ストレスで 脆弱な部位を明らかにした
- 遺伝子体,複製のタイミング,遺伝子機能に対するRDCの位置を分析した.
主要な成果:
- 27の再発性DSBクラスター (RDCs) が特定され,すべて遺伝子体内に位置しています.
- ほとんどのNSPCRDCは複製ストレス下で検出され,複製に関連した脆弱な部位を強調した.
- RDCは長さ,転写,後期複製遺伝子で主に発生しました.
- RDCを含む遺伝子のほぼ90%がシナプス機能および/または神経細胞の結合に関与しています.
- これらの遺伝子のかなりの部分は,腫瘍抑制および/または精神障害に関与しています.
結論:
- NSPC RDCの特徴は,神経細胞における遺伝子の脆弱性の基礎についての洞察を提供します.
- DNAの破損は神経発達と神経機能に 影響を及ぼし,神経学的および精神的障害に 繋がる可能性がある.
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