ABUNDANT DISORDER. “That it is essential to understand the interaction patterns of proteins with large intrinsically disordered segments becomes evident in the light of their abundance in higher eukaryotes (about 30–40% of their proteins contain large disordered segments) and the finding that proteins enriched in disorder are crucial for cellular processes such as transcription and signal transduction.”
http://www.biochemj.org/content/454/3/361?sa=X&ved=0CDkQ9QEwEWoVChMIzdjAo5n2xgIVovRyCh0HSAum