Johan Elf and colleagues developed a single-molecule chase assay to measure the time a single transcription factor is bound at a specific chromosomal operator site, which they use to examine the dynamics of binding of the Lac repressor dimer at the native lac operator in Escherichia coli. Their findings do not support the simple operator occupancy model and suggest a role for non-equilibrium transcription factor kinetics in E. coli gene regulation.
- Petter Hammar
- Mats Walldén
- Johan Elf
