Protein-protein interaction network rewiring across environments

(3) Mutable PPIs populate a newly-discovered and distinct “accessory” module of the protein interactome that is loosely connected, highly dynamic, and enriched for proteins involved in transcription, RNA processing, and translation (4) Mutable PPIs have several features that distinguish them from immutable PPIs: they are less likely to co-express, co-localize, and be explained by simple mass action kinetics, and more likely to contain intrinsically disordered regions, evolve quickly, and be of low abundance in standard conditions.

These results settle a long-standing debate concerning the statistical robustness of a “date hub/party hub” dichotomy and its implications for modularity of PPI networks (Han et al., Nature, 2004, 430: 88-93). Taken together, our results suggest that protein interactomes contain previously uncharacterized and highly dynamic regions that reorganize in response to cellular changes, and that this reorganization is due, to a larger extent, by post translational modifications.