Organized by unstructured motifs The high degree of conservation in protein sequences thought to be unstructured has hinted that these regions may have important biological functions. Although unstructured regions are widely viewed to be crucial for protein signaling, localization, and stability, their roles in many other settings have remained mysterious. Cermakova et al . discovered that prominent members of the transcription elongation machinery are linked through a network of interactions involving transcription elongation factor TFIIS N-terminal domains (TNDs) and conserved unstructured sequences called “TND-interacting motifs” (TIMs). The researchers found that mutation of a single TIM in a central organizing protein of this network abolished key protein interactions and induced widespread defects in transcription elongation dynamics. —DJ