世代を超えたエピジェネティック不安定性は,新しいメチル化変異の源である
Robert J Schmitz1, Matthew D Schultz, Mathew G Lewsey
1Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
まとめ
DNAメチル化における自発的な表遺伝的変化は,植物において世代を超えて発生することがあります. これらのDNAメチル化変異は,新しいエピアレルにつながり,遺伝的変異なしに表型多様性を駆動します.
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
- 植物生物学 植物生物学
背景:
- サイトシンDNAメチレーションは,表型情報の保存と継承のための重要な表遺伝的メカニズムです.
- DNAメチル化の変化は,遺伝子の転写と生物の形態学に影響を与える安定したエピアレルにつながる可能性があります.
- DNAメチル化の自発的増加または減少率は,ほとんど不明です.
研究 の 目的:
- DNAメチル化における自発的な表遺伝子変異を調査する.
- 世代を超えてDNAメチル化変化の速度を定量化するために.
- 現象型多様性におけるエピジェネティック・バリエーションの役割を理解する.
主な方法:
- アラビドプシス・タリアナ (Arabidopsis thaliana) の植物は,30世代に渡って単種の子孫として繁殖した.
- DNAメチル化パターンを分析するために,全ゲノムビスルファイト配列解析を使用した.
- 単一メチル化ポリモルフィズムと微分メチル化領域 (DMR) の識別と分析.
主要な成果:
- 114,287のCG単一メチル化ポリモルフィズムが特定されました.
- 2485 CGの微分メチル化領域 (DMR) が発見されました.
- 祖先状態と比較してメチレーションポリモルフィズムとDMRの相違パターンが観察されました.
結論:
- DNAメチル化における世代を超えたエピジェネティック変異は,自発的に発生する.
- これらのエピジェネティックの変化は,新しいエピアレル状態を生成することができます.
- エピジェネティック・バリエーションは,遺伝的変異から独立して現象型多様性のメカニズムを提供します.
関連する概念動画
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X-chromosome...
Epigenetic Regulation
Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
Epigenetic Regulation
Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
Inheritance of Chromatin Structures
Epigenetics is the study of inherited changes in a cell's phenotype without changing the DNA sequences. It provides a form of memory for the differential gene expression pattern to maintain cell lineage, position-effect variegation, dosage compensation, and maintenance of chromatin structures such as telomeres and centromeres. For example, the structure and location of the centromere on chromosomes are epigenetically inherited. Its functionality is not dictated or ensured by the underlying DNA...
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