アナフェーズカルシウム信号は,初期の海の胚の染色体分離を制御する

L Groigno¹, M Whitaker

¹Department of Physiological Sciences, University of Newcastle Upon Tyne Medical School, United Kingdom.

Cell

|February 11, 1998

まとめ

細胞内カルシウム濃度の一時的な増加は,海の胚アナフェーズ中に染色体分離を誘発する. このカルシウム信号は染色体解離に不可欠であり,細胞サイクル進行における重要な役割を明らかにしています.

科学分野:

細胞生物学細胞生物学
発達生物学発達生物学について
分子生物学は分子生物学である.

背景:

細胞サイクル進行には,染色体分離のような重要なイベントが含まれます.
カルシウムイオン (Ca2+) は,様々な細胞プロセスにおけるシグナル伝達分子として知られています.
アナフェーズイベントの開始におけるカルシウムの正確な役割は,まだ完全に理解されていません.

研究の目的:

海の胚におけるアナフェーズ発症を誘発する細胞内カルシウムトランジエントの役割を調査する.
カルシウムシグナル伝達がクロマチド解離とスパインドル延長の前提条件であるかどうかを判断する.

主な方法:

カルシウムケレーターとヘパリン (InsP3受容体アンタゴニスト) のマイクロ注射.
カルシウムとイノシトール三酸塩 (InsP3) のフォトリレーゼ (InsP3).
染色体分離,スパインドル延長,核リフォームの観察.

主要な成果:

細胞内カルシウム濃度 ([Ca2+]i) の一時的な増加は,染色体の解離とスパインドルの延長に先行する.
カルシウムシグナル伝達の阻害は染色体分離を阻害した.
カルシウムまたはInsP3のレベルが回復すると,ブロックが逆転した.
カルシウムアンタゴニストは核リフォーメーションを遅らせたが,ブロックすることはなかった.

結論:

カルシウム信号は,アナフェーズ中の染色体解離の重要なトリガーです.
カルシウムに依存しない経路は,マイクロチューブル動力学とアナフェーズにおける核イベントに寄与する.
この発見は,以前の矛盾した結果を説明し,異なる細胞タイプにおけるアナフェーズにおけるカルシウムの役割が保存されていることを示唆しています.

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