関連する実験動画
Updated: May 8, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
レチノブラストームのタンパク質と哺乳類のD型サイクリンとの機能的相互作用
Cell
|May 7, 1993
まとめ
サイクリンD2およびD3タンパク質は,腫瘍抑制剤であるレチノブラストーマタンパク質 (Rb) に結合する. この結合はRbのリン酸化につながり,細胞サイクル進行とE2F結合に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 細胞サイクル規制について
- がん生物学 がん生物学
背景:
- 網膜芽細胞腫タンパク質 (Rb) は,細胞循環制御に関与する重要な腫瘍抑制剤である.
- D型サイクリンは,サイクリン依存キナーゼ (CDK) と相互作用することで,細胞サイクル進行を調節する.
- RbとD型サイクリンの間の相互作用は疑われるが,完全に解明されていない.
研究 の 目的:
- 網膜芽細胞腫タンパク質 (Rb) と異なるD型サイクリン (D1,D2,D3) の間の特定の相互作用を調査する.
- これらの相互作用がRb活性と細胞サイクル進行に及ぼす機能的影響を決定する.
- Rb.の腫瘍抑制機能の調節における特定のD型サイクリンの役割を特定する.
主な方法:
- RbとD型サイクリン間の相互作用を評価するためのインビトロ結合測定法.
- 昆虫の細胞におけるサイクリンとCDK (cdk4,cdk2) の共発は,キナーゼ活性について研究する.
- Rb欠乏SAOS-2細胞にサイクリンD2とRbを導入し,Rbのリン酸化と細胞サイクル効果を観察する.
主要な成果:
- Rbは,D型サイクリンD2およびD3と効率的に相互作用したが,D1は,in vitroでは相互作用しなかった.
- サイクリンD2とD3は,cdk2と共に,サイクリンD1.1とは異なり,SAOS-2細胞におけるRb高リン酸化を誘導した.
- サイクリンD2媒介によるRb酸化は,RbのE2Fへの結合を減少させ,G1細胞サイクル停止を逆転させた.
結論:
- D型サイクリンには,Rb調節に関して同等の機能はありません.
- サイクリンD2は,Rb.の腫瘍抑制活性を調節する上で重要な役割を果たします.
- これらの発見は,D型サイクリンが細胞サイクル制御と潜在的に癌の発症に影響を与える特定のメカニズムを強調しています.
関連する概念動画
01:23Negative Regulator Molecules
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
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...
02:38Mitogens and the Cell Cycle
Mitogens and their receptors play a crucial role in controlling the progression of the cell cycle. However, the loss of mitogenic control over cell division leads to tumor formation. Therefore, mitogens and mitogen receptors play an important role in cancer research. For instance, the epidermal growth factor (EGF) - a type of mitogen and its transmembrane receptor (EGFR), decides the fate of the cell's proliferation. When EGF binds to EGFR, a member of the ErbB family of tyrosine kinase...
01:20The Retinoblastoma Gene
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
01:20The Retinoblastoma Gene
Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...