The effects of the deletion of VDAC on the physical properties and proteome of the mitochondrial outer membrane in Neurospora crassa

Abstract

Mitochondria are essential organelles in the cell. They are enveloped by a two membrane system, an inner and outer membrane. Residing in the outer membrane is the voltage-dependant anion-selective channel (VDAC) which is in very high abundance in the outer membrane. Previously, when VDAC was deleted in N. crassa the mitochondria developed unusual morphology and the fungus became temperature sensitive. This was suspected to be caused by alterations in the membrane architecture. It was found that deletion of VDAC causes a reduction in mitochondrial outer membrane fluidity leading to a fragile outer membrane. In the current study it was also found that loss of VDAC significantly impacts the mitochondrial proteome. These results taken together suggest that VDAC is not only a channel for traversing the outer membrane but appears to be important for the structural integrity of the mitochondria.