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セントロメアパラドックス:急速に進化するDNAと安定した遺伝.
S Henikoff1, K Ahmad, H S Malik
1Howard Hughes Medical Institute Research Laboratories, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA.
Science (New York, N.Y.)
|August 11, 2001
まとめ
ユカリオット染色体は,細胞分裂時に適切な分離のためにセントロメアに依存しています. セントロメリッククロマチンの急速な進化は,種の分岐と生殖分離を促す可能性があります.
科学分野:
- 遺伝学 遺伝学とは
- 細胞生物学 細胞生物学
- 進化生物学の進化生物学について
背景:
- セントロメアは,真核生物のミトーシスとメオシス中の正確な分離のために不可欠な染色体領域である.
- DNA配列は伝統的に遺伝的位置を定義しているが,セントロメアは,クロマチン経由で表遺伝的に受け継がれることがますます理解されている.
- 染色体分離のための分子機構は保存されていますが,センターメリックDNAとタンパク質の成分は急速に進化しています.
研究 の 目的:
- セントロメア特異化におけるクロマチンベースの遺伝子の役割を調査する.
- セントロメリック成分の進化動態と,その種の形成への潜在的影響を探求する.
主な方法:
- 保存された染色体分離装置の分析.
- ユカリオット種間のセントロメリッククロマチンの比較ゲノミクスとプロテオミクス.
- 急速に進化するセンターメリック因子間の不適合性を調査する.
主要な成果:
- 証拠は,DNA配列に対するセントロメア同一性のためのクロマチンベースの遺伝モデルを支持しています.
- セントロメリッククロマチンの特定のDNAとタンパク質成分の急速な進化が観察されました.
- これらの進化するコンポーネントの間の潜在的な不一致が特定されました.
結論:
- セントロメア機能は,固定されたDNA配列ではなく,クロマチンベースのエピジェネティックメカニズムに依存しています.
- セントロメリッククロマチン成分の急速な進化は,不適合性につながる可能性があります.
- これらの相容れない点は,センターメリック領域の組織化と新生種における生殖的孤立に寄与する可能性がある.
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