ヒトのCDC25タンパク質によるp34cdc2/cyclin B複合体の脱酸化と活性化 in vitro
U Strausfeld1, J C Labbé, D Fesquet
1CNRS and INSERM, BP 5051, Montpellier, France.
Nature
|May 16, 1991
まとめ
研究者らは,細胞分裂を活性化する重要なタンパク質を特定した. 人間のCDC25タンパク質は,p34cdc2/cyclin B複合体を分解して活性化させ,G2からM段階への細胞サイクル移行を促進します.
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.
- バイオケミストリー バイオケミストリー
背景:
- 不活性なp34cdc2/サイクリンB複合体によるG2相における卵細胞の停止.
- この複合体は,p34cdc2.2.のリン酸化によって不活性化されます.
- これを調節するフォスファテーゼは不明だが,CDC25は活性化因子である可能性が高い.
研究 の 目的:
- p34cdc2/cyclin B複合体の活性化におけるCDC25の役割を調査する.
- ヒトのCDC25が複合体を in vitroで活性化できるかどうかを判断する.
主な方法:
- 不活性なp34cdc2/サイクリンB複合体の海星卵細胞からの浄化.
- 精製されたバクテリアで発現したヒトp54CDC25H.を使用したインビトロ測定法.
主要な成果:
- p54CDC25Hを添加すると,p34cdc2脱酸化が誘発される.
- 複合体のp54CDC25H活性化されたH1ヒストンキナーゼ活性.
結論:
- cdc25+遺伝子製品は,p34cdc2-サイクリンB複合体を直接活性化します.
- 人間のp54CDC25Hは,海星卵細胞p34cdc2-サイクリンB複合体を機能的に活性化することができます.
関連する概念動画
01:45Positive Regulator Molecules
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
02:39Positive Regulator Molecules
Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
02:34Inhibition of Cdk Activity
The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
02:17Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
00:50Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
02:34Inhibition of CDK Activity
The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...