Kv1 potassium channel complexes in vivo require Kvbeta2 subunits in dorsal spinal neurons.
Kv1 potassium channel complexes in vivo require Kvbeta2 subunits in dorsal spinal neurons.
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DOI：
10.1152/jn.90667.2008
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发表时间：
2008-10
影响因子：
2.5
通讯作者：
Ricardo H. Pineda;Christopher S. Knoeckel;Alison D. Taylor;A. Estrada-Bernal;A. Ribera
中科院分区：
文献类型：
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作者：
Ricardo H. Pineda;Christopher S. Knoeckel;Alison D. Taylor;A. Estrada-Bernal;A. Ribera
而Kv β 2亚基调节钾电流的性质进行Kv 1通道复合物在异源系统中，鲜为人知的是Kv β 2亚基的贡献，天然钾通道功能。利用反义方法和原位记录从非洲爪蟾胚胎脊髓神经元，我们测试了在体内的作用Kv β 2亚基的电压依赖性钾电流（IKv）的调制。我们集中在1）两个不同的群体的背脊髓神经元，表达Kv β 2和Kv 1 α亚基基因和2）24小时和48小时的发育期，在此期间IKv经历发育调节。在24和48小时，反义方法产生了有效的敲低Kv β 2蛋白和IKv。在这两个时间，显性负性抑制Kv 1通道也消除了IKv，表明Kv 1通道需要Kv β 2亚基在脊髓背侧神经元中发挥作用。尽管Kv 1通道决定了两种背神经元类型的IKv值，但它们的IKv特性的比较揭示了两个发育阶段的重要差异。后者的结果支持的概念，不同的Kv 1 α-亚基和/或翻译后修饰的IKV值的两个背神经元类型的基础。总体而言，结果表明，Kv β 2亚基在体内至少两种神经元类型和两个不同的发育阶段中作为Kv 1通道的专性亚基起作用。
Whereas Kvbeta2 subunits modulate potassium current properties carried by Kv1 channel complexes in heterologous systems, little is known about the contributions of Kvbeta2 subunits to native potassium channel function. Using antisense approaches and in situ recordings from Xenopus embryo spinal cord neurons, we tested the in vivo roles of Kvbeta2 subunits in modulation of voltage-dependent potassium current (IKv). We focused on 1) two different populations of dorsal spinal neurons that express both Kvbeta2 and Kv1 alpha-subunit genes and 2) the 24- and 48-h developmental period, during which IKv undergoes developmental regulation. At both 24 and 48 h, antisense methods produced efficient knock-down of both Kvbeta2 protein and IKv. At both times, dominant negative suppression of Kv1 channels also eliminated IKv, indicating that Kv1 channels require Kvbeta2 subunits to function in dorsal spinal neurons. Even though Kv1 channels determined the IKv values of both dorsal neuron types, comparisons of their IKv properties revealed important differences at both developmental stages. The latter results support the notion that different Kv1 alpha-subunits and/or posttranslational modifications underlie the IKv values of the two dorsal neuron types. Overall, the results demonstrate that Kvbeta2 subunits function in vivo as obligatory subunits of Kv1 channels in at least two neuron types and two different developmental stages.