Spatial Dynamics of Chromosome Translocations in Living Cells

Abstract

Chromosome Choreography Chromosome translocations arise through the illegitimate pairing of broken chromosome ends and are commonly found in many cancers. Roukos et al. (p. 660 ) used ultrahigh-throughput time-lapse imaging on human tissue culture cells containing marked chromosomes to capture very rare translocation events. Double-strand breaks in the DNA underwent an initial “partner search,” with a fraction of the ends moving into spatial proximity to each other, which resulted in persistent pairing and the merging of DNA repair foci. Most paired ends arose from breaks in close proximity, but occasionally translocations formed from more distantly positioned breaks. Proteins of the DNA repair machinery could influence the pairing and/or translocation process.