Consequences of dimerization of the voltage-gated proton channel.
Consequences of dimerization of the voltage-gated proton channel.
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DOI：
10.1016/b978-0-12-386931-9.00012-x
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发表时间：
2013
影响因子：
--
通讯作者：
DeCoursey, Thomas E.
中科院分区：
文献类型：
--
作者：
Smith, Susan M. E.;DeCoursey, Thomas E.
人类电压门控质子通道hHV1似乎主要以二聚体形式存在。目的，这是令人费解的，因为每个原聚体保留的主要特性，这种蛋白质的特点：质子传导，是由构象（通道打开和关闭）的变化，发生在响应电压和pH值的HV1二聚体主要是由C端卷曲螺旋相互作用。几种类型的突变产生单体构建体，其打开速度比WT二聚体通道快约5倍，但具有较弱的电压依赖性。有趣的是，HV1二聚体的典型功能，打开允许H+传导，合作发生。两个原体都经历构象变化，但在任何一个可以导电之前都必须经历这种转变。二聚化的目的可能是使通道开放的电压依赖性变陡，至少在吞噬细胞中是这样。在其他细胞中，目的不被理解。最后，一些单细胞物种的HV可能是单体的。
The human voltage gated proton channel, hHV1, appears to exist mainly as a dimer. Teleologically, this is puzzling, because each protomer retains the main properties that characterize this protein: proton conduction that is regulated by conformational (channel opening and closing) changes that occur in response to both voltage and pH. The HV1 dimer is mainly linked by C terminal coiled-coil interactions. Several types of mutations produce monomeric constructs that open ~5 times faster than the WT dimeric channel, but with weaker voltage dependence. Intriguingly, the quintessential function of the HV1 dimer, opening to allow H+ conduction, occurs cooperatively. Both protomers undergo a conformational change, but both must undergo this transition before either can conduct. The teleological purpose of dimerization may be to steepen the voltage-dependence of channel opening, at least in phagocytes. In other cells, the purpose is not understood. Finally, several single-celled species have HV that are likely monomeric.