Applications of proteomics
In the preceding chapters, we have discussed a range of different technologies that allow proteins to be studied on a large scale. These technologies can be applied in two major ways. The ﬁrst type of application involves the systematic identiﬁcation and quantitation of all the proteins found in a particular cell, tissue or organism. This approach lies at the core of systems biology and the ultimate aim is to provide a complete quantitative breakdown of the proteome including all post-translational variants. A more focused version of this approach is to ﬁnd differences between related samples, i.e. differences in protein proﬁles that accompany changes in physiological states. The second type of application involves the investigation of protein functions and interactions, and includes a diverse range of experimental methods such as the analysis of protein sequences, structures, interactions and biochemical activities. When these global, discovery-driven methods are combined, they inevitably better our understanding of many biological processes. Already we are seeing how this new knowledge can be applied in medicine, agriculture and industry.