RecA finds homologous DNA by reduced dimensionality search.

ABSTRACT: Homologous recombination is essential for the accurate repair of double-stranded DNA breaks (DSBs)¹. Initially, the RecBCD complex² resects the ends of the DSB into 3' single-stranded DNA on which a RecA filament assembles³. Next, the filament locates the homologous repair template on the sister chromosome⁴. Here we directly visualize the repair of DSBs in single cells, using high-throughput microfluidics and fluorescence microscopy. We find that, in Escherichia coli, repair of DSBs between segregated sister loci is completed in 15 ± 5 min (mean ± s.d.) with minimal fitness loss. We further show that the search takes less than 9 ± 3 min (mean ± s.d) and is mediated by a thin, highly dynamic RecA filament that stretches throughout the cell. We pro

SUBMITTER: Wiktor J 

PROVIDER: S-EPMC8443446 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature