德洛索菲拉S6激酶:细胞大小的调节剂
J Montagne1, M J Stewart, H Stocker
1Friedrich Miescher Institute, Maulbeerstrasse 66, 4058 Basel, Switzerland.
Science (New York, N.Y.)
|September 25, 1999
概括
多虫中的S6激酶基因 (dS6K) 调节细胞大小,确保细胞在分裂前达到关键大小. 这种基因产物可以自主控制细胞生长,而不会影响细胞数量.
科学领域:
- 细胞生物学 细胞生物学
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
背景情况:
- 细胞增殖取决于细胞生长到临界大小.
- 调节细胞生长和维护大小的机制尚未完全理解.
- 细胞大小是影响生物过程的基本参数.
研究的目的:
- 为了研究草 S6 激酶基因 (dS6K) 在调节细胞大小中的作用.
- 阐明DS6K影响细胞生长和发育的机制.
- 为了确定dS6K是否在控制细胞大小方面具有细胞自主作用.
主要方法:
- 对缺乏S6激酶基因 (dS6K) 的Drosophila melanogaster突变物的分析.
- 在dS6K突变体中,发育延迟和体型减小的表型特征.
- 细胞大小和细胞数量在dS6K突变和野生类型之间进行比较.
- 区分dS6K与核糖体蛋白突变体的影响 (分钟).
主要成果:
- 缺乏dS6K的青虫表现出极端的发育延迟和身体尺寸的减少.
- 突变的表现出更小的细胞,而不是更少的细胞,表明细胞大小缺陷.
- 观察到对细胞大小的影响是细胞自主性的.
- dS6K基因产物在细胞大小调节中的作用与核糖体蛋白突变物不同.
结论:
- 德罗斯菲拉S6激酶 (dS6K) 基因产物对于调节细胞大小至关重要.
- dS6K以细胞自主的方式控制细胞生长.
- dS6K 调节细胞大小独立于细胞数量,影响整个生物体的发育.
相关概念视频
01:45Positive Regulator Molecules
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
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...
02:36Cells Coordinate Growth and Proliferation
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
01:28The Cell Cycle Control System
The cell cycle regulation directs how a cell proceeds from one phase to the next and begins mitosis. The cell cycle control system includes intracellular regulatory molecules and external triggers. They provide "stop" or "advance" signals and operate at specific cell cycle stages termed checkpoints to ensure that a particular process is completed before the cell advances to the next phase.
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...
Cyclins and cyclin-dependent kinases (Cdks) are the primary cell cycle regulators and function at the cell...