Indirect stimulation of recombination in Escherichia coli K-12: dependence on recJ, uvrA, and uvrD.
AUTOR(ES)
Schellhorn, H E
RESUMO
Direct and indirect UV-stimulated homologous genetic recombination was investigated in Escherichia coli strains blocked in several host-encoded functions. Genetic recombination was assayed by measuring beta-galactosidase produced after recombination between two noncomplementing lacZ ochre alleles. Both types of stimulation (direct and indirect) were found to be primarily RecF pathway-mediated. In a rec+ background, both direct and indirect stimulation were found to be dependent on uvrD (coding for helicase II). In a recB21 sbcB15 background, direct and indirect stimulation were uvrD dependent only when the strain was additionally deficient in the UvrABC excision repair pathway. Indirect but not direct stimulation was also dependent on recJ (coding for a 5'-to-3' exonuclease specific for single-stranded DNA) regardless of sbcA or sbcB configuration. The methyl-directed mismatch repair system (mutSLH) also appeared to play an important role in stimulation. On the basis of these findings, we suggest that excision of UV-induced DNA damage is a prelude to UV-mediated stimulation of genetic recombination.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=208370Documentos Relacionados
- Involvement of genes uvrD and recB in separate mutagenic deoxyribonucleic acid repair pathways in Escherichia coli K-12 uvrB5 and B/r uvrA155.
- Effects of recJ, recQ, and recFOR Mutations on Recombination in Nuclease-Deficient recB recD Double Mutants of Escherichia coli
- Roles of RecJ, RecO, and RecR in RecET-Mediated Illegitimate Recombination in Escherichia coli
- Genetic analysis of the recJ gene of Escherichia coli K-12.
- Influence of uvrD3, uvrE502, and recL152 mutations on the phenotypes of Escherichia coli K-12 dam mutants.