相关实验视频
Updated: Jun 26, 2026

07:51
Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
单个卡尔莫杜林分子的依赖质的平衡波动
Jan Philipp Junker1, Fabian Ziegler, Matthias Rief
1Physik Department E22, Technische Universität München, James-Franck-Strasse, 85748 München, Germany.
概括
单分子力谱学揭示了离子和如何影响calmodulin.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 蛋白质动力学 蛋白质动力学
背景情况:
- 卡尔莫杜林 (CaM) 是一种关键的真核生物依赖的信号转换器.
- 了解CaM的结构变化是解读其监管作用的关键.
- 机械力量提供了一种独特的方法来探测蛋白质能量景观.
研究的目的:
- 为了研究单个卡尔莫杜林分子的机械特性和连接体相互作用.
- 在不同的条件下绘制calmodulin的能量格局.
- 实时观察酸与calmodulin的结合动态.
主要方法:
- 使用定制的低漂移原子力显微镜进行单分子力光谱.
- 对单个卡尔莫杜林分子施加受控的机械负荷.
- 分析了结构平衡波动来重建能量景观.
主要成果:
- 发现离子会影响单个CaM域的折叠动力学.
- 目标可以稳定calmodulin的折叠结构.
- 确定了结合固态度和合作性:黄蜂毒 (非合作性, 2:1),酶 (合作性, 1:1).
- 当机械负荷直接应用于目标时,观察到实时的结合/解结合过渡.
结论:
- 单分子力谱学为calmodulin的机械行为和连接体相互作用提供了详细的见解.
- 干结合显著调节calmodulin的结构格局和动态.
- 该技术允许实时观察动态绑定事件.
相关概念视频
Calmodulin-dependent Signaling
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,...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
The Equilibrium Binding Constant and Binding Strength
The equilibrium binding constant (Kb) quantifies the strength of a protein-ligand interaction. Kb can be calculated as follows when the reaction is at equilibrium:
The Equilibrium Binding Constant and Binding Strength
The equilibrium binding constant (Kb) quantifies the strength of a protein-ligand interaction. Kb can be calculated as follows when the reaction is at equilibrium:
Feedback Regulation of Calcium Concentration
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...
