細胞内自由カルシウムの上昇は,海の胚の核封筒分解を誘発する
1Department of Zoology, University of California, Berkeley 94720.
Nature
|March 24, 1988
まとめ
細胞内自由カルシウム[Ca2+]iの増加は,ミトーシスの調節に不可欠である. カルシウムの増加を遮断すると,核包膜分解 (NEBD) が防止され,細胞分裂が止まりますが,カルシウムレベルを回復すると,ミトーシスが再開できます.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学とは
背景:
- サイトソリックフリーカルシウム ([Ca2+]i) は,様々な細胞のミトーシスの調節に作用する.
- 以前の研究では,[Ca2+]iの増加と核包膜分解 (NEBD) とアナフェーズ発現のような主要なミトーシスイベントの間の相関が観察されました.
研究 の 目的:
- ミトーシスを調節する[Ca2+]i増加の因果的役割を実験的に決定する.
- 核包膜分解 (NEBD) に対する前代謝[Ca2+]i上昇の必要性を調査する.
主な方法:
- カルシウム・ケレーター緩衝溶液を海の胚に微量注入して,細胞内自由カルシウムレベルを操作する.
- カルシウム操作後の核包膜分解 (NEBD) とミトス進行の観察とタイミング.
主要な成果:
- NEBDの前に[Ca2+]iの自然な増加をブロックすることで,NEBDを予防し,ミトーシスを停止しました.
- その後,注射または自然回復によって[Ca2+]iレベルを回復させることで,NEBDを救出し,ミトーシスの進行を可能にしました.
- 細胞サイクル初期に[Ca2+]iを人工的に上昇させると,早発性NEBDが誘発される.
結論:
- 核包膜分解 (NEBD) に先立つ細胞内自由カルシウム ([Ca2+]i) の増加は,重要な規制イベントである.
- このカルシウムの上昇は,ミトーシスの開始と進行に不可欠です.
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