Mitochondrial shuttle

The mitochondrial shuttles are systems used to transport reducing agents across the inner mitochondrial membrane. NADH cannot cross the membrane, but it can reduce another molecule that can cross the membrane, so that its electrons can reach the electron transport chain. The mitochondrial shuttles are systems used to transport reducing agents across the inner mitochondrial membrane. NADH cannot cross the membrane, but it can reduce another molecule that can cross the membrane, so that its electrons can reach the electron transport chain.