ヘテロクロマチンと表遺伝子制御における転置可能な元素の役割
Zachary Lippman1, Anne-Valérie Gendrel, Michael Black
1Watson School of Biological Sciences and Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA.
Nature
|July 23, 2004
まとめ
アラビドプシスのヘテロクロマチンは,主にDDM1.1によって調節される転置可能な元素と繰り返しで構成されています. 小さな干渉RNAs (siRNAs) は,おそらくこのプロセスをガイドし,遺伝子発現に影響を与えます.
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
- 分子生物学は分子生物学である.
背景:
- ヘテロクロマチンは,凝縮された染色体物質によって特徴づけられ,セントロメアとテロメアの近くに存在します.
- インタースティシャルヘテロクロマチン (ノブ) は,植物ゲノム,特にトウモロコシに多く見られ,反復性であり,後期的に複製される.
- 遺伝子発現におけるヘテロクロマチンの役割は,ドロソフィラの位置効果変異によって示され,規制機能を示唆しています.
研究 の 目的:
- アラビドプシスのヘテロクロマチンの組成と調節を調査する.
- ヘテロクロマチン形成と遺伝子調節における移植可能な元素と小干渉RNA (siRNAs) の役割を調査する.
- 移植可能な要素と関連するクロマチンの改造因子による遺伝子の表遺伝的調節を理解する.
主な方法:
- ヘテロクロマティック配列を特定するためのマイクロアレイ分析.
- ヘテロクロマティック領域に対応する小さな干渉RNA (siRNA) の分析.
- インプリントされた遺伝子FWA.の表遺伝的調節を調査する.
主要な成果:
- アラビドプシスのヘテロクロマチンは,トランスポーザブルな要素とタンデムリピートによって決定され,クロマチンを改造するATPase DDM1 (DNAメチル化減少1) によって制御されます.
- 小型の干渉RNA (siRNAs) はこれらの異色配列に対応し,DDM1.1を誘導する役割を示唆しています.
- 移植可能な要素は,遺伝子の内部またはその近くに挿入されると,遺伝子を表遺伝子学的に調節することができ,DDM1およびMET1のインプリントされた遺伝子FWAの調節を説明します.
結論:
- アラビドプシスのヘテロクロマチンは,DDM1によって調節され,siRNAsによって導かれる,転置可能な元素と繰り返しから大きく構成されています.
- 移植可能な要素は,特に遺伝子プロモーターの近くに位置すると,表遺伝子遺伝子調節に重要な役割を果たします.
- この研究は,ヘテロクロマチン形成の基礎となる分子機構と,植物における遺伝子発現と発達への影響を明らかにしています.
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