Proteome analysis. I. Gene products are where the biological action is

Two-dimensional electrophoresis has rapidly become the method of choice for resolving complex mixtures of proteins. Since the technique was pioneered in 1975, 2-D gel methods have undergone a series of enhancements to optimize resolution and reproducibility. Recent improvements in the sensitivity of mass spectrometry have allowed the direct identification of polypeptides from 2-D gels by a procedure termed "mass profiling". In combination, these two techniques have made possible the characterization of the complete collection of gene products, or proteome, of an organism. Proteomes are increasingly being documented as interactive informational databases available on the World Wide Web (WWW). This availability of organismic global protein patterns will no doubt be an invaluable resource aiding the discovery of diagnostic and therapeutic disease markers.