Organelles, expression specific

Aside from molecular and biophysical properties of proteins such as mass and charge, all proteins share common attributes that are directly related to the ability or inability to perform global protein analysis. In particular, the spatial context of a particular proteome represents a large part of the complexity for proteomic analysis (Figure 4.3) since total protein expression may relate to an organism, a specific organ, a tissue, a cell, a subcellular organelle, or even biofluid. 

Due to the limitations of prediction, there is a need for projects that will collect data on subcellular location for a variety of conditions. These projects determine protein location rather than predict it. Although these projects are useful in their own right, they also serve as a way to expand the database for the prediction of protein location. One powerful approach to determination is to isolate specific organelles or stmctures and then identify their components by expression proteomics methods (Bmnet et al. 2003). This provides information rapidly for large numbers of proteins but has limited ability to distinguish different domains within an organelle. This chapter will focus on a complementary approach, automated determination of subcellular location using fluorescence microscopy. 

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