芽生えた酵母菌のミトーシス中に,一時的な姉妹染色体分離と染色体の弾性変形が起こる
1Massachusetts Institute of Technology, Department of Biology, Cambridge 02139, USA.
Cell
|July 13, 2000
まとめ
ミトーシスにおける正確な染色体分離は,正しいキネトコアと微小管の結合に依存しています. 酵母染色体は,一時的な姉妹分離を示し,センターメリック染色体を明らかにします.
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.
- 遺伝学 遺伝学とは
背景:
- 正確な染色体分離は,細胞分裂に不可欠です.
- 姉妹染色体結合は,アナフェーズ前に解消されなければならない.
- キネトコアと微小管の結合は,染色体の並び合わせにおいて重要な役割を果たします.
研究 の 目的:
- 染色体分離におけるキネトコア-マイクロチューブル結合の役割を調査する.
- S. cerevisiae.のGFPタグされた染色体の動きを分析する.
- ミトーシス中の一時的な姉妹分離のメカニズムを理解するために.
主な方法:
- S. cerevisiae.のGFPタグされた染色体の生細胞画像.
- 染色体とキネトコアタンパク質の動きの分析.
- セントロメリッククロマチン分離と持続時間の測定.
主要な成果:
- キネトコアと微小管の結合は,姉妹染色体を一時的に分離させる緊張を生成する.
- 暫定的な分離は2〜10分持続し,コヘシンタンパク質分解の前に発生します.
- 姉妹染色体は分離時に独立して移動し,その後,結合を再確立します.
結論:
- 酵母における一時的な姉妹分離は,キネトコア-マイクロチューブル張力によって引き起こされる.
- この現象は,キネトコアタンパク質のバイロベッドの局所化を説明する.
- イーストのセントロメリッククロマチンは,動物の細胞に似たテンシオメーターとして機能する可能性があります.
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