Proteomic Studies of the Intrinsically Unstructured Mammalian Proteome

Intrinsically unstructured proteins (IUPs) represent an important class of proteins primarily involved in
cellular signaling and regulation. The aim of this study was to develop methodology for the enrichment
and identification of IUPs. We show that heat treatment of NIH3T3 mouse fibroblast cell extracts at 98
°C selects for IUPs. The majority of these IUPs were cytosolic or nuclear proteins involved in cell signaling
or regulation. These studies represent the first large-scale experimental investigation of the intrinsically
unstructured mammalian proteome.
Keywords: intrinsically unstructured proteins • disordered proteins • proteomics • mammalian proteome • heat
denaturation