CaT1表现出释放激活通道的孔状性质
1Children's Hospital, Harvard Medical School, Enders 1309, 320 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|April 5, 2001
概括
研究人员将CaT1蛋白确定为释放激活通道 (ICRAC). CaT1表现出独特的生物物理特性,证实其在信号通路中的作用.
科学领域:
- 分子生物学分子生物学
- 细胞生理学 细胞生理学
- 离子通道研究研究
背景情况:
- 释放激活通道 (ICRAC) 对于细胞信号传递至关重要.
- 它独特的封闭性使其成为研究信号传导的关键目标.
- 对ICRAC的分子鉴定仍然难以捉摸,阻碍了详细的调查.
研究的目的:
- 为了确定负责ICRAC活动的分子成分.
- 描述已识别的蛋白质的生物物理特性.
- 确认已识别的蛋白质是否表现出ICRAC通道特征.
主要方法:
- 哺乳动物细胞中CaT1蛋白的表达.
- 电生理学记录以评估离子通道功能.
- 将CaT1的生物物理特性与已知的ICRAC通道行为进行比较.
主要成果:
- 表达的CaT1蛋白显示了Ca2+的选择性和通过细胞内Ca2+的减少激活.
- 在较高的细胞内Ca2+度下,CaT1表现出无活化,反映了ICRAC.
- 像异常摩尔分数效应和块等关键特征与ICRAC一致.
结论:
- CaT1蛋白具有ICRAC通道的特征生物物理特性.
- 建议CaT1构成ICRAC孔的全部或部分.
- 这种识别为研究信号传导和相关疾病开辟了新的途径.
相关概念视频
G-Protein Gated Ion Channels
5.5K
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...
5.5K
Feedback Regulation of Calcium Concentration
2.9K
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...
2.9K
Calmodulin-dependent Signaling
5.0K
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,...
5.0K
Catenins
2.2K
Catenins are characterized by multiple binding domains and dynamic structures that allow them to function as linker proteins in cell junction complexes. All catenins, except α-catenin, contain a characteristic protein sequence called the armadillo repeat and are therefore also called armadillo proteins.
Catenins in Cell Junctions
Catenins bind to cell adhesion molecules such as cadherins and link them to different cytoskeletal proteins depending on the type of cell junction. At the...
Catenins in Cell Junctions
Catenins bind to cell adhesion molecules such as cadherins and link them to different cytoskeletal proteins depending on the type of cell junction. At the...
2.2K
Ligand-Gated Ion Channel Receptor: Gating Mechanism
4.6K
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...
4.6K
Synthesis and Functions of Calcitonin
4.8K
Calcitonin, a vital polypeptide hormone, regulates calcium levels within body fluids. It is released by the parafollicular cells, also known as C cells, situated in the follicular epithelium of the thyroid gland. Calcitonin responds to fluctuations in blood calcium levels and the influence of gastrointestinal hormones like gastrin and cholecystokinin.
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...
4.8K


