在鱼的轴突中,通过ATP-gamma-S对细胞内pH调节系统的pH敏感激活
W F Boron1, E Hogan, J M Russell
1Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06510.
Nature
|March 17, 1988
概括
细胞内pH调节对于细胞功能至关重要. 这项研究表明,ATP激活了依赖的化物 - 二碳酸盐交换器,对pH平衡至关重要,而不是被它消耗.
科学领域:
- 细胞生理学 细胞生理学
- 膜运输 运输 膜运输
- 生物化学 生物化学
背景情况:
- 细胞内pH (pHi) 调节对于细胞功能和激活至关重要.
- 在许多细胞类型中,依赖于的化物-二碳酸盐交换是主要的pHi调节器.
- 在鱼轴突中对这种交换器的ATP要求在机理上仍然不清楚.
研究的目的:
- 阐明ATP在依赖的化物 - 二碳酸盐交换器的功能中的作用.
- 为了区分ATP水解 (假设) 和ATP激活 (激活假设) 对于传送器功能.
主要方法:
- 用不可水解的ATP模拟物ATP-gamma-S.对鱼轴突进行透析.
- 通过Na+依赖的Cl-HCO3-交换器调节的ATP在pH调节中的作用的研究.
主要成果:
- 这项研究排除了假说,证明ATP并非经体积计消耗.
- 结果表明,需要ATP来激活交换器的pH值.
- 激活可以通过酸化或直接通过ATP与载体或激活剂结合来发生.
结论:
- ATP对于激活依赖的化物-二碳酸盐交换器至关重要,而不是通过水解直接提供能量.
- 这些发现澄清了细胞pH稳态和细胞激活过程中的关键机制.
相关概念视频
Action Potentials
Overview
ATP Driven Pumps I: An Overview
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
Action Potential
Neurons communicate by firing action potentials—the electrochemical signal that is propagated along the axon. The signal results in the release of neurotransmitters at axon terminals, thereby transmitting information to the nervous system. An action potential is a specific "all-or-none" change in membrane potential that results in a rapid spike in voltage.
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
ATP Driven Pumps III: V-type Pumps
V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
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...
Action Potential
Neurons communicate by firing action potentials—the electrochemical signal that is propagated along the axon. The signal results in the release of neurotransmitters at axon terminals, thereby transmitting information to the nervous system. An action potential is a specific "all-or-none" change in membrane potential that results in a rapid spike in voltage.
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...
Membrane potential in neurons
Neurons typically have a resting membrane potential of about -70 millivolts (mV). When they receive...


