相关实验视频
Updated: Jun 6, 2026

08:51
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
异构体循环核酸门通道采用3A:1B的固体测量方法
Haining Zhong1, Laurie L Molday, Robert S Molday
1Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Nature
|November 15, 2002
概括
对于感官至关重要的循环核酸 (CNG) 通道,被发现具有3A:1B子单位比,而不是2A:2B. 这一发现是由A子单元中的新型CLZ域驱动的,重新定义了CNG通道结构和功能.
科学领域:
- 生物物理学的生物物理.
- 分子生物学分子生物学
- 神经科学是一个神经科学.
背景情况:
- 循环核酸入 (CNG) 通道对于视觉和嗅觉中的信号传导至关重要.
- 原生CNG通道是四度体,通常由A和B子单元组成,假设2A:2B静态度.
研究的目的:
- 为了研究异构CNG通道的子单元固体测量.
- 识别CNG通道中介于CNG通道内的子单位间相互作用的新领域.
主要方法:
- 在CNG通道A子单元中的碳氧终端氨酸拉链 (CLZ) 域的识别和表征.
- 交叉连接,非变质凝电泳和分析超离心法来评估子单元之间的相互作用.
- 具有改变CLZ域的突变CNG通道的功能分析.
主要成果:
- 该CLZ域介导特异于A子单元的三元相互作用.
- 突变道与三元氨酸拉链取代CLZ模仿野生类型的行为.
- 牛杆CNG通道的生物化学分析证实了3A:1B的静脉测量.
结论:
- 异构CNG通道的原生静态度是3A:1B,挑战了长期以来的2A:2B模型.
- 这一CLZ域对于建立3A:1B固体几何学至关重要.
- 这种修订后的固体几何学为理解CNG道结构功能关系提供了一个新的框架.
相关概念视频
G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
G-protein Coupled Receptors
G-protein coupled receptors are ligand binding receptors that indirectly affect changes in the cell. The actual receptor is a single polypeptide that transverses the cell membrane seven times creating intracellular and extracellular loops. The extracellular loops create a ligand specific pocket which binds to neurotransmitters or hormones. The intracellular loops holds onto the G-protein.
Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
G-Protein Gated Ion Channels
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 organs,...
Sensory organs,...
Structure of Cadherins
The cadherins were one of the first cell adhesion molecules discovered; the term “cadherins” is based on their calcium-dependent adhering properties. The first cadherins discovered on the epithelial, neuronal, and placental cells were named E-cadherin, P-cadherin, and N-cadherin, respectively. These classical cadherins share sequence and structural similarities. Other cadherins, including those involved in cell signaling, are grouped into non-classical cadherins. This diversity of cadherins...
Ligand-Gated Ion Channel Receptor: Gating Mechanism
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...

