Department of Physiology & Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
Nat Neurosci. 2010 Mar;13(3):333-7. doi: 10.1038/nn.2493. Epub 2010 Feb 14.
Kv4 low voltage-activated A-type potassium channels are widely expressed in excitable cells, where they control action potential firing, dendritic activity and synaptic integration. Kv4 channels exist as a complex that includes K(+) channel-interacting proteins (KChIPs), which contain calcium-binding domains and therefore have the potential to confer calcium dependence on the Kv4 channel. We found that T-type calcium channels and Kv4 channels form a signaling complex in rat that efficiently couples calcium influx to KChIP3 to modulate Kv4 function. This interaction was critical for allowing Kv4 channels to function in the subthreshold membrane potential range to regulate neuronal firing properties. The widespread expression of these channels and accessory proteins indicates that the Cav3-Kv4 signaling complex is important for the function of a wide range of electrically excitable cells.
Kv4 低电压激活的 A 型钾通道广泛表达于可兴奋细胞，在这些细胞中，它们控制动作电位的发放、树突活动和突触整合。Kv4 通道作为一个复合物存在，包括 K(+)通道相互作用蛋白（KChIPs），其包含钙结合结构域，因此有可能赋予 Kv4 通道钙依赖性。我们发现，T 型钙通道和 Kv4 通道在大鼠中形成一个信号复合物，有效地将钙内流与 KChIP3 偶联，从而调节 Kv4 功能。这种相互作用对于允许 Kv4 通道在亚阈膜电位范围内发挥作用以调节神经元发放特性至关重要。这些通道和辅助蛋白的广泛表达表明，Cav3-Kv4 信号复合物对于广泛的电兴奋细胞的功能很重要。
