The mitochondrial calcium uniporter (MCU) and the mitochondrial calcium uniporter dominant negative b- subunit (MCUb) are pore-forming components of the uniporter complex. We expressed these MCU subunits in cell-free transcription/translation systems, and we studied them, at the single molecule level, using the electrophysiological technique of planar lipid bilayer.
We showed that MCU gives rise to single-channel Ca2+ currents. In contrast, MCUb alone does not display calcium-permeable channel activity, while the co-expression of MCUb:MCU drastically alters the calcium permeation mediated by MCU subunit.
Planar lipid bilayer Ion channel Calcium signaling
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