Department of Medicine and Microbiology, College of Medicine, Signaling Disorder Research Center, Chungbuk National University, Cheongju 361-763, Korea.
BMB Rep. 2010 Oct;43(10):677-82. doi: 10.5483/BMBRep.2010.43.10.677.
Kv4.2, a pore-forming α-subunit of voltage-gated A-type potassium channels, is expressed abundantly in the soma and dendrites of hippocampal neurons, and is responsible for somatodendritic I(A) current. Recent studies have suggested that changes in the surface levels of Kv4.2 potassium channels might be relevant to synaptic plasticity. Although the function and expression of Kv4.2 protein have been extensively studied, the dendritic localization of Kv4.2 mRNA is not well described. In this study, Kv4.2 mRNAs were shown to be localized in the dendrites near postsynaptic regions. The dendritic transport of Kv4.2 mRNAs were mediated by microtubule- based movement. The 500 nucleotides of specific regions within the 3'-untranslated region of Kv4.2 mRNA were found to be necessary and sufficient for its dendritic localization. Collectively, these results suggest that the dendritic localization of Kv4.2 mRNAs might regulate the dendritic surface level of Kv4.2 channels and synaptic plasticity.
Kv4.2 是电压门控 A 型钾通道的一种孔形成 α 亚基，在海马神经元的体和树突中大量表达，负责产生体树突 I(A)电流。最近的研究表明，Kv4.2 钾通道表面水平的变化可能与突触可塑性有关。尽管 Kv4.2 蛋白的功能和表达已被广泛研究，但 Kv4.2 mRNA 的树突定位尚未得到很好的描述。在这项研究中，Kv4.2 mRNA 被证明定位于靠近突触后区域的树突中。Kv4.2 mRNA 的树突运输是由微管为基础的运动介导的。发现 Kv4.2 mRNA 的 3'-非翻译区的特定区域内的 500 个核苷酸对于其树突定位是必需和充分的。总的来说，这些结果表明，Kv4.2 mRNA 的树突定位可能调节 Kv4.2 通道的树突表面水平和突触可塑性。
