ヒストン遺伝子の欠損がSaccharomyces cerevisiaeにおけるクロマチンの構造に及ぼす影響

D Norris¹, B Dunn, M A Osley

¹Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA.

Science (New York, N.Y.)

|November 4, 1988

まとめ

Saccharomyces cerevisiaeにおけるヒストン変異体の調査は,局所的なクロマチンの破壊を明らかにした. これは,酵母菌のゲノム全体に差異的な核細胞の組み立てと維持を示唆しています.

科学分野:

分子生物学は分子生物学である.
遺伝学遺伝学とは
イースト生物学イースト生物学

背景:

核子の組立と維持は,ゲノムの安定性にとって極めて重要です.
ヒストンH2AとH2Bは核細胞の重要な構成要素である.
イーストミュータントの研究は,基本的な細胞のプロセスを理解するのに役立ちます.

研究の目的:

ヒストンH2AとH2Bの核細胞組立と維持における役割を調査する.
クロマチンの構造が変化した酵母変異体を特定するために.
細胞のフェノタイプに対するクロマチンの破壊の影響を理解する.

主な方法:

ヒストンH2AおよびH2Bのための遺伝子削除または重複を有するSaccharomyces cerevisiae変異体の分析.
重要な現象型を持つ変異体を特定するための遺伝分析.
核細胞組織を評価するためのクロマチンの構造分析.

主要な成果:

1つの特定の変異体は,破壊されたクロマチンに関連した劇的なプレオトロプ的フェノタイプを示した.
クロマチン破壊は,グローバルではなく,特定のゲノム領域に局限していた.
核細胞組織は,HIS4,GAL1遺伝子,テロメア,Ty要素では正常だったが,CYH2,UBI4遺伝子,および染色体IIIのセントロメアでは障害があった.

結論:

局所的なクロマチンの破壊は,酵母ゲノム全体で異なる核細胞組立/維持機構を暗示しています.
特定のゲノム領域は,ニュクレオソームの組織に対する明確な要求を持つ可能性があります.
ヒストン遺伝子の変異は,重要な現象的結果をもたらす地域特有の染色体欠陥につながる可能性があります.

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