What makes a mitochondrion?
With the completion of the genome sequences of yeast, human and Arabidopsis, which contain approximately 6,000, 35,000 and 28,000 genes, respectively [1-3], the world’s attention is now shifting to elucidation of gene function, and major proteomic studies are currently under way on a variety of organisms [4-6]. As a step towards assembling a list of the total complement of proteins in any one cell type (its proteome), proteomic studies of subcellular compartments and organelles have become a major focus, because smaller and more manageable subsets of proteins are involved. Given that compartmentation is a hallmark of the eukaryotic cell, and because the functions of organelles are biochemically well defined, such studies have an immediate functional impact, in contrast to the relatively limited insights that can be gained from the complete, unstructured cell proteome. Mitochondria are attractive targets for subcellular proteomics because they play vital roles in energy production, anab
