Disease relevance of ruvB

• BACKGROUND: All the ruvA, ruvB and ruvC mutants of Escherichia coli are sensitive to treatments that damage DNA, and are mildly defective in homologous recombination [1].
• We report here the cloning of the ruvB gene from a thermophilic eubacterium, Thermus thermophilus HB8 (Tth), and the biochemical characterization of the gene product expressed in E. coli [2].

High impact information on ruvB

• The Escherichia coli ruvA and ruvB genes are involved in DNA repair and in the late step of homologous genetic recombination [3].
• Molecular characterization of the locus revealed that there are three genes--ruvA, ruvB and ruvC; mutations in any one of the genes confer the same phenotype [4].
• K68R, K68A, and T69A mutants except T69S failed to complement UV-sensitive phenotype of the ruvB strain [5].
• To elucidate the role of the Walker motif A of RuvB (GXGKT; X indicates a nonconserved residue) in ATP hydrolysis and branch migration activities, we constructed four ruvB mutant genes by site-directed mutagenesis, altering the highly conserved Lys(68) and Thr(69) [5].
• In this study, we isolated a large number of plasmids carrying ruvB mutant genes and identified amino acid residues important for the RuvB functions by examining the in vivo DNA repair activities of the mutant proteins [6].

Biological context of ruvB

• Each of the two open reading frames, designated ruvA and ruvB, is preceded by a reasonable Shine-Dalgarno sequence [7].
• Two 16 bp sequences (SOS boxes) that match the consensus sequence for binding LexA protein are located 5' to ruvA in a region that provides a possible single promoter for expression of both ruvA and ruvB, with the second SOS box overlapping the putative -35 region [7].
• Surprisingly, the uvrD deletion completely suppressed the phenotype of a ruvB mutation in a recBCsbcB(C) background [8].
• The SOS-inducible ruvA and ruvB gene products of Escherichia coli are required for normal levels of genetic recombination and DNA repair [9].
• The ruvA and ruvB genes of Escherichia coli constitute an operon which belongs to the SOS regulon [10].

Other interactions of ruvB

• B. burgdorferi ruvB is part of an operon which comprises the homologues of ruvA, queA and pfbB [11].
• Expression of the B. burgdorferi ruvB and ruvA genes renders a wild-type Escherichia coli sensitive to UV light and mitomycin, indicative of negative complementation. priA, which encodes the potential recognition factor for the primosome assembly site, was found at 15 kbp from the left telomere [11].

Analytical, diagnostic and therapeutic context of ruvB

• To gain insight into the mechanism of branch migration, random mutations were introduced into the ruvB gene by PCR and a collection of mutant alleles were obtained [12].

References