Mitochondrial complex I in the network of known and unknown facts

The mitochondrial respiratory chain consists of five multi-subunit complexes embedded in the inner mitochondrial membrane. Complex 1 is the largest and most complicated proton pump of the respiratory chain encoded by both the mitochondrial and nuclear genomes. In this minireview, attention is given to recent knowledge on the structure, catalytic properties, supramolecular organisation of complex I and its possible role in the triggering of apoptosis.