对于KCa2.2通道激活器的亚型选择性的结构基础
Young-Woo Nam1,2, Alena Ramanishka1,2, Yang Xu3
1Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, USA.
Nature communications
|January 8, 2026
概括
冷-EM结构揭示了NS309和rimtuzalcap如何与激活通道 (KCa2.2和KCa3.1) 相结合. 这些发现解释了rimtuzalcap的发现.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- 小导电性 (KCa2.2) 和中导电性 (KCa3.1) 激活通道是关键的药物标.
- 这些通道由和素调节,影响细胞刺激能力.
- 像NS309和rimtuzalcap这样的调节剂对KCa2.2和KCa3.1.1.具有差异性的影响.
研究的目的:
- 阐明rimtuzalcap对KCa2.2通道的亚型选择性的结构基础.
- 了解NS309.9对KCa2.2和KCa3.1的强化背后的分子机制.
- 为开发新型KCa2.2-向治疗提供结构性基础.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定高分辨率结构.
- 对KCa2.2和KCa3.1通道与NS309和rimtuzalcap结合的结构分析.
- 对KCa3.1突变体 (R355K) 的研究,以评估药物结合.
主要成果:
- 确定了与NS309结合的KCa2.2/KCa3.1和与rimtuzalcap结合的KCa2.2.2.的冷EM结构.
- 鉴定出不同的calmodulin和细胞质螺旋形状,负责rimtuzalcap的KCa2.2选择性.
- 揭示了NS309与预先形成的口袋结合,而rimtuzalcap利用KCa2.2.2.中的诱导适合机制.
- 证明了一个KCa3.1_R355K突变能够使rimtuzalcap结合.
结论:
- 卡尔莫杜林和HC螺旋的结构差异决定了rimtuzalcap选择性的KCa2.2激活.
- 由于它与先前存在的口袋相互作用,NS309具有更广泛的结合能力.
- 这些结构为基于结构的药物设计提供蓝图,针对神经系统疾病的KCa2.2通道.
相关概念视频
Ligand-Gated Ion Channel Receptor: Gating Mechanism
3.8K
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...
3.8K
Calmodulin-dependent Signaling
6.0K
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,...
6.0K
Voltage-gated Ion Channels
10.3K
Voltage-gated ion channels are transmembrane proteins that open and close in response to changes in the membrane potential. They are present on the membranes of all electrically excitable cells such as neurons, heart, and muscle cells.
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several...
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several...
10.3K
Secondary Active Transport
9.3K
One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this process is sodium (Na+), which is typically present in higher concentrations extracellularly than in the cytosol. Such a concentration difference is due, in part, to the action of an enzyme "pump" embedded in the cellular membrane that actively expels Na+ from a cell. Importantly, as this pump contributes to the high concentration of...
9.3K
The Role of Ion Channels in Neuronal Computation
3.6K
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential....
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential....
3.6K
Ligand-gated Ion Channels
13.9K
Ligand-gated ion channels are transmembrane proteins with a channel for ions to pass through and a binding site for a ligand. The channel opens only when a ligand attaches to the binding site.
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that...
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that...
13.9K


