Preliminary Characterization of VDAC3, an Elusive Member of the Outer Mitochondrial Membrane Pore Family

The VDAC (Voltage Dependent Anion selective Channel) family of proteins is composed of three evolutionary related isoforms in vertebrates [1-2]. Despite the sequence similarity, the functional data existing nowadays point to different functions for them. The isoforms are expressed at different levels [3], and show a different ability to complement the growth defect in yeast S. cerevisiae devoid of the endogenous porin [4], indicating that either they have different capacities to be translocated in the OMM or they have really different pore-forming activity, at least when expressed in S.