卡尔莫杜林将本地Ca2+信号进行分叉,从而调节P/Q型Ca2+通道
C D DeMaria1, T W Soong, B A Alseikhan
1The Johns Hopkins University School of Medicine, Departments of Biomedical Engineering and Neuroscience, Program in Molecular and Cellular Systems Physiology, 720 Rutland Avenue, Baltimore, Maryland 21205, USA.
Nature
|May 25, 2001
概括
卡尔莫杜林 (CaM) 独特地调节P/Q型通道,导致促进和非激活. 这种双重行动,由CaM调解.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 通道功能 通道功能
背景情况:
- 神经活动通过细胞内Ca2+调节P/Q型 (alpha1A) 通道.
- 这种调制对于短期的突触可塑性和大脑计算至关重要.
- 建议calmodulin (CaM) 在通道调制中发挥双重作用:促进和非激活.
研究的目的:
- 为了研究α1A通道的Ca2+依赖的CaM调节的机制.
- 确定CaM的Ca2+结合部位和叶片在道调节中的作用.
- 为了阐明CaM如何解码局部Ca2+信号以实现不同的通道调制.
主要方法:
- 研究了对alpha1A carboxy尾部的CaM结合,专注于类似IQ的域.
- 利用一个缺乏Ca2+结合位点的CaM突变体 (CaM1234) 来评估CaM的传感器作用.
- 分析了CaM的氨基末端和碳氧末端叶在道调制中的不同作用.
主要成果:
- 促进和非激活都需要Ca2+-CaM与IQ类域结合,而不是CBD网站.
- 一种缺乏Ca2+结合位点的CaM突变 (CaM1234) 消除了促进和非激活.
- CaM的N-叶会调解无活化,而它的C-叶会调解便利化,证明叶的特定信号传递.
结论:
- CaM作为Ca2+传感器,对α1A通道进行双重调节.
- CaM的双功能能力来自于叶片特定的Ca2+信号传输,明显地解码Ca2+信号.
- 这种机制为神经元提供了一种紧的方式来微调突触传输.
相关概念视频
G-Protein Gated Ion Channels
7.4K
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...
Sensory...
7.4K
IP3/DAG Signaling Pathway
16.1K
Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and...
16.1K
Feedback Regulation of Calcium Concentration
4.3K
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
4.3K
Calmodulin-dependent Signaling
7.2K
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
7.2K
Ligand-Gated Ion Channel Receptor: Gating Mechanism
5.0K
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
5.0K
Antihypertensive Drugs: Action of Calcium Channel Blockers
2.3K
Calcium ions are essential to contract smooth muscle cells in blood vessels. They enter these cells through voltage-dependent calcium channels, specifically L-type calcium channels in the cell membrane. These L-type calcium channels are integral to the excitation-contraction coupling process in smooth muscle. When a stimulus is received by smooth muscle cells, their membrane depolarizes. This alteration in membrane potential instigates the opening of L-type calcium channels. As a result,...
2.3K


