Resection of DNA double strand–break ends generates single strands that can spontaneously anneal to undergo mutagenic microhomology-mediated end joining (MMEJ). A combination of genetic and biophysical assays now shows that replication protein A (RPA) thwarts strand annealing by binding to the resected ends to promote Rad51 filament assembly and error-free repair by homologous recombination.
- Sarah K Deng
- Bryan Gibb
- Lorraine S Symington