細胞周期中のHeLa細胞のヒストンメッセンジャーRNAの合成

M Melli, G Spinelli, E Arnold

Cell

|September 1, 1977

まとめ

HeLa細胞ヒストンのメッセンジャーRNAは,DNA複製が阻害された場合でも,細胞サイクルを通して継続的に合成されます. サイトプラズマレベルは低いため,転写後の調節を示す.

科学分野:

分子生物学は分子生物学である.
細胞生物学細胞生物学
遺伝学遺伝学とは

背景:

ヒストンタンパク質はDNAの包装に不可欠であり,細胞周期のS相で合成されます.
以前の研究では,ヒストン遺伝子転写とDNA複製の間の潜在的なリンクが示唆されていました.

研究の目的:

ヘラ細胞におけるヒストンメッセンジャーRNA (mRNA) の合成と調節を細胞サイクル全体で調査する.
ヒストンのmRNA合成がDNA複製と結合しているかどうかを判断する.

主な方法:

再結合ファグにおける海ヒストンの遺伝子DNAにHeLa細胞RNAをハイブリッド化する.
細胞をDNA合成阻害剤であるサイトシンアラビノシドで治療する.

主要な成果:

ヒストンのmRNAは,HeLa細胞で細胞サイクル全体を通して合成されます.
ヒストンのmRNA合成は,DNA複製がサイトシンアラビノシドによって抑制された場合でも継続されます.
ヒストンRNAは核に存在しますが,細胞プラズマのレベルは著しく低下します.

結論:

ヒストンのmRNA合成は,HeLa細胞のDNA複製と結合していません.
細胞質ヒストンのmRNAレベルの調節は,転写中のではなく,転写後のレベルで起こります.

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