Proteomics: An Overview

The application of genomics has established a firm foundation for research into both human health and disease, and the development of proteomics was the next logical step, but what exactly is proteomics? The term proteomics was first coined in 1995 from a combination of “protein” and “genomics,” but it was far earlier in 1979 that the concept to fully characterize the human proteome was first proposed by Norman G. Anderson and N. Leigh Anderson in a submission entitled the “Human Proteins Index Project.”1 At that time it was hoped that, by using the newly developed technique of 2-dimensional gel electrophoresis (2D-PAGE), the genome would be unlocked through the proteins identified. Since then, like most things in the field of science, the understanding of proteomics has evolved. The term proteomics now encompasses the concept of completeness, the idea that all proteins should be identified and studied. Already 1 study that fully incorporates this concept of completeness is that by the Protein Structure Initiative of the National Institutes of General Medical Sciences (NIGMS). Its aim is to generate a comprehensive database of all protein structures found in nature (http://www.nigms.nih.gov). This aim, however, is beyond the scope and ability of all but the largest scientific consortiums, and so the logical progression from generic protein identification for most researchers is the analysis of those proteins present within a chosen tissue, or cell population, with the aim of developing pattern recognition of the proteins expressed. Any differences observed in protein expression between different tissues can be examined, and groups or individual proteins examined in greater detail. Such a technique could allow for the characterization of specific protein markers of inflammation that are differentially expressed between inflamed and noninflamed intestinal tissue, and perhaps the identification of cellular markers of malignant change. Because of the huge number of proteins expressed in any 1 tissue, such wide-ranging profiling would primarily use high-throughput technologies to characterize the changes. These findings, however, are merely a snap shot of the protein levels at a single moment in time, and determination of changes in protein expression and location over time would engender greater information.