Control of cross-over by single-strand DNA resection.
Control of DNA cross-overs is necessary for meiotic recombination and genome integrity. The frequency of cross-overs is dependent on homology length and the conversion tract, but the mechanisms underlying the regulation of cross-overs remain unknown. We propose that 5'-end resection, a key intermediate in double-strand break repair, could determine the formation of cross-overs. Extensive DNA resection might favor gene conversion without cross-over by channeling recombination events through synthesis-dependent strand-annealing. In reactions with short regions of homology, resection beyond the homologous sequence would impede Holliday junction formation and, consequently, cross-over. Extensive DNA resection could be an effective mechanism to prevent reciprocal exchanges between dispersed DNA sequences, and thus contribute to the genome stability.
Prado
Félix
F
Departamento de Genética, Facultad de Biologi;a, Universidad de Sevilla, 41012, Sevilla, Spain.
Aguilera
Andrés
A
D003434:Crossing Over, Genetic; D004260:DNA Repair; D005658:Fungi / Q000235:genetics*