ABSTRACT
Experimental evidence points to the disorder of about 500 proteins (Sickmeier et al. 2007), which is far short of the thousands of proteins predicted to harbor significant disorder in the human proteome alone (see Chapter 13, Section 13.1.1). Thus, critical progress in the field is expected from large-scale and rapid identification of fully or mostly disordered proteins by dedicated high-throughput screening (HTS) approaches. As outlined in this chapter, several studies have met these goals, but their results are not without limitations. A serious complicating factor comes from our lack of a clear definition of disorder (see Chapter 2, Section 2.1), due to which there can be no universal solution to the large-scale identification of IDPs, and the results need confirmation by independent approaches. A further level of ambiguity comes from the definition of disorder at the residue level, not the level of whole proteins. To succeed in identifying the disorder of regions as opposed to whole proteins, ordered and disordered regions should be delineated and separately studied. HTS studies, instead, work at the level of entire
proteins and provide binary information on whether the protein behaves as ordered, or rather as disordered, within the resolution of the technique.
