Gene expression: degrade to derepress.

Chromatin immunoprecipitation and sequencing (ChIP-seq) provides a static snap-shot of DNA-associated proteins which fails to reflect the dynamics of the DNA-bound proteome. Now, Catic and co-workers combine ubiquitin ChIP-seq and proteasome inhibitors to map sites of DNA-associated protein degradation on a genome-wide scale. They identify an ubiquitin ligase which targets a transcriptional repressor for destruction by the proteasome, thus activating transcription of specific genes. These findings reveal that the ubiquitin proteasome system actively regulates transcription.