Mitochondrial proteomics - Undercover in the lipid bilayer

Alteration of the mitochondrial proteome and altered mitochondrial function has been implicated in a variety of degenerative diseases, heart disease, aging and cancer. Based upon the human genome there is estimated to be approximately 1000 to 2000 proteins constituting the mitochondrial proteome. Despite the ability of a traditional proteomic approach involving two-dimensional gel electrophoresis (2-DE) to resolve and identify thousands of proteins in a single gel, just over 600 mitochondrial proteins have been identified and characterized at the molecular level. The limitations and recent advances of 2-DE in its ability to study mitochondrial proteins and create a database of the mitochondrial proteome is discussed, as well as the alternative methods that are being employed, including different mass spectrometry based approaches following both one-dimensional SDS-PAGE and gel-free approaches, blue native gel electrophoresis (BN-PAGE), proteome simplification by submitochondrial fractionation, and affinity chromatography. In addition, the successful application of proteomics to the investigation of some specific mitochondrial cardiomyopathies is discussed.