Castellano A, Chiara M D, Mellström B, Molina A, Monje F, Naranjo J R, López-Barneo J
Facultad de Medicina, Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, E-41009, Sevilla, Spain.
J Neurosci. 1997 Jun 15;17(12):4652-61. doi: 10.1523/JNEUROSCI.17-12-04652.1997.
The physiological diversity of K+ channels mainly depends on the expression of several genes encoding different alpha-subunits. We have cloned a new K+ channel alpha-subunit (Kv2.3r) that is unable to form functional channels on its own but that has a major regulatory function. Kv2.3r can coassemble selectively with other alpha-subunits to form functional heteromultimeric K+ channels with kinetic properties that differ from those of the parent channels. Kv2.3r is expressed exclusively in the brain, being concentrated particularly in neocortical neurons. The functional expression of this regulatory alpha-subunit represents a novel mechanism without precedents in voltage-gated channels, which might contribute to further increase the functional diversity of K+ channels necessary to specify the intrinsic electrical properties of individual neurons.
钾离子通道的生理多样性主要取决于几个编码不同α亚基的基因的表达。我们克隆了一种新的钾离子通道α亚基（Kv2.3r），它自身无法形成功能性通道，但具有主要的调节功能。Kv2.3r可以与其他α亚基选择性地共同组装，形成具有与亲本通道不同动力学特性的功能性异源多聚体钾离子通道。Kv2.3r仅在大脑中表达，尤其集中在新皮层神经元中。这种调节性α亚基的功能性表达代表了一种在电压门控通道中前所未有的新机制，这可能有助于进一步增加确定单个神经元内在电特性所需的钾离子通道的功能多样性。
