查看文章

Modulation of K⁺ channels is widely used to dynamically regulate neuronal membrane excitability. The voltage-gated K⁺ channel Kv2.1 is an abundant delayed rectifier K⁺ (I_K) channel expressed at high levels in many types of mammalian central neurons where it regulates diverse aspects of membrane excitability. Neuronal Kv2.1 is constitutively phosphorylated, localized in high-density somatodendritic clusters, and has a relatively depolarized voltage dependence of activation. Here, we show that the clustering and voltage-dependent gating of endogenous Kv2.1 in cultured rat hippocampal neurons are modulated by cholinergic stimulation, a common form of neuromodulation. The properties of neuronal Kv2.1 are recapitulated in recombinant Kv2.1 expressed in human embryonic kidney 293 (HEK293) cells, but not COS-1 cells, because of cell background-specific differences in Kv2.1 phosphorylation. As in …