@article {830,
	title = {dnaC mutations suppress defects in DNA replication- and recombination-associated functions in priB and priC double mutants in Escherichia coli K-12.},
	journal = {Mol Microbiol},
	volume = {34},
	year = {1999},
	month = {1999 Oct},
	pages = {91-101},
	abstract = {PriA, PriB and PriC were originally discovered as proteins essential for the PhiX174 in vitro DNA replication system. Recent studies have shown that PriA mutants are poorly viable, have high basal levels of SOS expression (SOSH), are recombination deficient (Rec-), sensitive to UV irradiation (UVS) and sensitive to rich media. These data suggest that priA{\textquoteright}s role may be more complex than previously thought and may involve both DNA replication and homologous recombination. Based on the PhiX174 system, mutations in priB and priC should cause phenotypes like those seen in priA2:kan mutants. To test this, mutations in priB and priC were constructed. We found that, contrary to the PhiX174 model, del(priB)302 and priC303:kan mutants have almost wild-type phenotypes. Most unexpectedly, we then found that the priBC double mutant had very poor viability and/or a slow growth rate (even less than a priA2:kan mutant). This suggests that priB and priC have a redundant and important role in Escherichia coli. The priA2:kan suppressor, dnaC809, partially suppressed the poor viability/slow growth phenotype of the priBC double mutant. The resulting triple mutant (priBC dnaC809 ) had small colony size, recombination deficiency and levels of SOS expression similar to a priA2:kan mutant. The priBC dnaC809 mutant, however, was moderately UVR and had good viability, unlike a priA2:kan mutant. Additional mutations in the triple mutant were selected to suppress the slow growth phenotype. One suppressor restored all phenotypes tested to nearly wild-type levels. This mutation was identified as dnaC820 (K178N) [mapping just downstream of dnaC809 (E176G)]. Experiments suggest that dnaC820 makes dnaC809 suppression of priA and or priBC mutants priB and or priC independent. A model is proposed for the roles of these proteins in terms of restarting collapsed replication forks from recombinational intermediates.},
	keywords = {Bacterial Proteins, Bacteriophage mu, Cell Division, DNA Replication, DNA, Bacterial, DNA-Binding Proteins, Escherichia coli, Escherichia coli Proteins, Mutation, Phenotype, Recombination, Genetic, Replication Protein A, SOS Response (Genetics), Substrate Specificity, Suppression, Genetic},
	issn = {0950-382X},
	author = {Sandler, S J and Marians, K J and Zavitz, K H and Coutu, J and Parent, M A and Clark, A J}
}
@article {838,
	title = {recO and recR mutations delay induction of the SOS response in Escherichia coli.},
	journal = {Mol Gen Genet},
	volume = {246},
	year = {1995},
	month = {1995 Jan 20},
	pages = {254-8},
	abstract = {RecF, RecO and RecR, three of the important proteins of the RecF pathway of recombination, are also needed for repair of DNA damage due to UV irradiation. recF mutants are not proficient in cleaving LexA repressor in vivo following DNA damage: therefore they show a delay of induction of the SOS response. In this communication, by measuring the in vivo levels of LexA repressor using anti-LexA antibodies, we show that recO and recR mutant strains are also not proficient in LexA cleavage reactions. In addition, we show that recO and recR mutations delay induction of beta-galactosidase activity expressed from a lexA-regulated promoter following exposure of cells to UV, thus further supporting the idea that recF, recO and recR gene products are needed for induction of the SOS response.},
	keywords = {Bacterial Proteins, beta-Galactosidase, DNA-Binding Proteins, Escherichia coli, Escherichia coli Proteins, Gene Expression Regulation, Bacterial, Mutation, Promoter Regions, Genetic, Recombinant Fusion Proteins, Repressor Proteins, Serine Endopeptidases, SOS Response (Genetics), Ultraviolet Rays},
	issn = {0026-8925},
	author = {Hegde, S and Sandler, S J and Clark, A J and Madiraju, M V}
}
@article {843,
	title = {Use of high and low level overexpression plasmids to test mutant alleles of the recF gene of Escherichia coli K-12 for partial activity.},
	journal = {Genetics},
	volume = {135},
	year = {1993},
	month = {1993 Nov},
	pages = {643-54},
	abstract = {We showed that sufficient overexpression of the wild-type recF gene interfered with three normal cell functions: (1) UV induction of transcription from the LexA-protein-repressed sulA promoter, (2) UV resistance and (3) cell viability at 42 degrees. To show this, we altered a low-level overexpressing recF+ plasmid with a set of structurally neutral mutations that increased the rate of expression of recF. The resulting high-level overexpressing plasmid interfered with UV induction of the sulA promoter, as did the low-level overexpressing plasmid. It also reduced UV resistance more than its low level progenitor and decreased viability at 42 degrees, an effect not seen with the low-level plasmid. We used the high-level plasmid to test four recF structural mutations for residual activity. The structural alleles consisted of an insertion mutation, two single amino acid substitution mutations and a double amino acid substitution mutation. On the Escherichia coli chromosome the three substitution mutations acted similarly to a recF deletion in reducing UV resistance in a recB21 recC22 sbcB15 sbcC201 genetic background. By this test, therefore, all three appeared to be null alleles. Measurements of conjugational recombination revealed, however, that the three substitution mutations may have residual activity. On the high-level overexpressing plasmid all three substitution mutations definitely showed partial activity. By contrast, the insertion mutation on the high-level overexpressing plasmid showed no partial activity and can be considered a true null mutation. One of the substitutions, recF143, showed a property attributable to a leaky mutation. Another substitution, recF4101, may block selectively two of the three interference phenotypes, thus allowing us to infer a mechanism for them.},
	keywords = {Alleles, Bacterial Proteins, Base Sequence, Chromosomes, Bacterial, DNA Repair, DNA, Bacterial, DNA-Binding Proteins, Escherichia coli, Escherichia coli Proteins, Gene Expression, Genes, Bacterial, Molecular Sequence Data, Mutagenesis, Site-Directed, Mutation, Phenotype, Plasmids, Radiation Tolerance, Recombination, Genetic, Ultraviolet Rays},
	issn = {0016-6731},
	author = {Sandler, S J and Clark, A J}
}
@article {847,
	title = {Genes of the RecE and RecF pathways of conjugational recombination in Escherichia coli.},
	journal = {Cold Spring Harb Symp Quant Biol},
	volume = {49},
	year = {1984},
	month = {1984},
	pages = {453-62},
	keywords = {Chromosome Mapping, Conjugation, Genetic, Escherichia coli, Genes, Bacterial, Mutation, Protein Biosynthesis, Recombination, Genetic},
	issn = {0091-7451},
	author = {Clark, A J and Sandler, S J and Willis, D K and Chu, C C and Blanar, M A and Lovett, S T}
}
@article {846,
	title = {Molecular analysis of the recF gene of Escherichia coli.},
	journal = {Proc Natl Acad Sci U S A},
	volume = {81},
	year = {1984},
	month = {1984 Aug},
	pages = {4622-6},
	abstract = {We analyzed the nucleotide sequence of a 1.325-kilobase region of wild-type Escherichia coli containing a functional recF gene and six Tn3 mutations that inactivate recF. The analysis shows a potentially translatable reading frame of 1071 nucleotides, which is interrupted by all six insertions. A protein of 40.5 kilodaltons would result from translation of the open reading frame, and a radioactive band of protein of an apparent molecular weight of approximately 40 kilodaltons was seen by the maxicell method using a recF+ plasmid. Putative truncated peptides were seen when two recF::Tn3 mutant plasmids were used. Differential expression of dnaN and recF from a common promoter was noted. recF332::Tn3 was transferred to the chromosome where, in hemizygous condition, it produced UV sensitivity indistinguishable from that produced by two presumed recF point mutations.},
	keywords = {Amino Acid Sequence, Bacterial Proteins, Base Sequence, DNA Repair, DNA Replication, Escherichia coli, Genes, Bacterial, Molecular Weight, Mutation, Plasmids, Recombination, Genetic},
	issn = {0027-8424},
	author = {Blanar, M A and Sandler, S J and Armengod, M E and Ream, L W and Clark, A J}
}
