RecA finds homologous DNA by reduced dimensionality search

• DOI: 10.1038/s41586-021-03877-6
• Publication Date: 2021-09-01T16:03:44Z
• Authors: Jakub Wiktor; Arvid H. Gynnå; Prune Leroy; Jimmy Larsson; Giovanna Coceano; Ilaria Testa; Johan Elf
• Keywords: DNA, Bacterial; 0301 basic medicine; Time Factors; Bioinformatics and Systems Biology; Bioinformatics and Computational Biology; DNA, Single-Stranded; Recombinational DNA Repair; Bioinformatik och systembiologi; Models, Biological; Article; 3. Good health; Rec A Recombinases; 03 medical and health sciences; Bioinformatik och beräkningsbiologi; Sequence Homology, Nucleic Acid; Escherichia coli; DNA Breaks, Double-Stranded

Abstract Homologous recombination is essential for the accurate repair of double-stranded DNA breaks (DSBs) 1 . Initially, RecBCD complex 2 resects ends DSB into 3′ single-stranded on which a RecA filament assembles 3 Next, locates homologous template sister chromosome 4 Here we directly visualize DSBs in single cells, using high-throughput microfluidics and fluorescence microscopy. We find that, Escherichia coli , between segregated loci completed 15 ± 5 min (mean s.d.) with minimal fitness loss. further show that search takes less than 9 s.d) mediated by thin, highly dynamic stretches throughout cell. propose architecture effectively reduces dimensionality. This model predicts time consistent our measurement corroborated observation does not depend length cell or amount DNA. Given abundance homologues believe this to be widely conserved across living organisms.