Transcriptional Silencers in Drosophila Serve a Dual Role as Transcriptional Enhancers in Alternate Cellular Contexts (Molecular Cell)

Gisselbrecht et al. performed a screen in developing Drosophila embryos for genomic sequences that can act as transcriptional silencers. They report that nearly all silencers are enhancers in other tissues or at other developmental stages. Their silencers fall into two classes, one of which forms physical chromosomal contacts with promoters.