不受精卵で複製する能力は,Cdc6によって,中性成熟期中に授与される
Jean-Marc Lemaître1, Stéphane Bocquet, Marcel Méchali
1Institute of Human Genetics, CNRS, Genome Dynamics and Development, 141 Rue de la Cardonille, 34396 Montpellier Cedex 5, France.
Nature
|October 18, 2002
まとめ
クセノプスの卵の成熟において,Cdc6タンパク質合成はDNA複製に不可欠である. このプロセスは成熟時に起因し,受精前に卵がDNAを複製することを可能にし,Cdc6が鍵となる要因である.
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:
- 卵巣の成熟は卵細胞の発達に不可欠であり,未成熟の卵細胞を受精可能な卵に変容させます.
- Xenopusの卵細胞の成熟の間に,DNA複製能力は,核包膜の崩壊後の獲得されます.
- 卵細胞に存在しない特定のDNA合成誘発体は,成熟時に翻訳される.
研究 の 目的:
- クセノプスの卵における複製能力に責任を負うDNA合成誘導体を特定する.
- 卵細胞の成熟時にDNA複製を開始するCdc6の役割を明らかにする.
主な方法:
- DNA合成誘導体としてCdc6の識別.
- 母親のcdc6 mRNAと卵細胞内のタンパク質貯蔵の分析.
- オリゴヌクレオチドアンチセンセ注射と翻訳阻害により,Cdc6合成を阻害する.
- 再結合Cdc6タンパク質を用いた救助実験.
主要な成果:
- Cdc6は,ミニクロモソーム維持 (MCM) ヘリケーゼの徴募に不可欠であると特定されています.
- 母親のcdc6 mRNAが貯蔵され,成熟時にCdc6タンパク質が合成されます.
- Cdc6の翻訳は,DNA複製能力のために必要かつ十分である.
- 細胞静止因子 (CSF) 経路は,受精までS相への入り口を防ぐ.
結論:
- 中性成熟期におけるCdc6翻訳は,Xenopusの卵にDNA複製能力を与える重要な出来事です.
- Cdc6は,合成が翻訳的に調節される唯一の必要で十分な複製因子として作用します.
- 複製の許可はメヨシスIの終わりに発生するが,CSFはS相への入り口を積極的に阻害する.
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