1 School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK.
2 Department of Pharmacology and Chemical Biology, University of Pittsburgh, University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, Pennsylvania 15213, USA.
Repair enzymes must communicate across hundreds of nucleotides to undo errors made during DNA replication. Imaging reveals that the enzymes do this by forming a series of ring-like clamps that diffuse along the DNA.