Disease relevance of rdgB

• This gene, rdgB (for Rec-dependent growth), mapped near 64 min on the E. coli genetic map [1].
• Nucleotide sequence, organization and expression of rdgA and rdgB genes that regulate pectin lyase production in the plant pathogenic bacterium Erwinia carotovora subsp. carotovora in response to DNA-damaging agents [2].

High impact information on rdgB

• The rdgB recA lethality is suppressed by inactivation of endonuclease V (gpnfi) specific for DNA-hypoxanthines/xanthines, suggesting that RdgB either intercepts improper DNA precursors dITP/dXTP or works downstream of EndoV in excision repair of incorporated hypoxathines/xanthines [3].
• Here we characterize one such mutant, rdgB/yggV, deficient in a putative inosine/xanthosine triphosphatase, conserved throughout kingdoms of life [3].
• Based upon sequence homology, rdgA was predicted to encode a repressor and rdgB was presumed to specify a transcriptional activator [4].
• We found neither a significant increase in spontaneous mutagenesis in rdgB and nfi single mutants or the double mutant nor any changes in nitrous acid-induced mutagenesis for rdgB mutant strains [5].
• The E. coli rdgB gene encodes a protein homologous to a deoxyribonucleotide triphosphate pyrophosphatase from Methanococcus jannaschii that shows a preference for purine base analogs. moa rdgB mutants are extremely sensitive to killing by HAP and exhibit increased mutagenesis, recombination, and SOS induction upon HAP exposure [6].

Biological context of rdgB

• The cloned gene suppresses the hyper-Rec phenotype and the enhanced level of SOS functions in rdgB mutants at the nonpermissive temperature [7].
• The ability of a plasmid to complement an rdgB recA mutant was correlated with its ability to produce a 25-kilodalton polypeptide as detected by the maxicell technique [1].
• The kinetic data presented here also show that transcription of pnlA followed that of rdgB in Er. carotovora subsp. carotovora, indicating a temporal order of gene expression [8].
• The findings reported here, taken along with our previous observation that the rdgE product is required for pnlA expression, establishes that rdgB encodes a transcriptional factor which specifically interacts with the pnlA promoter/regulatory region [8].
• The activation of pectin lyase (Pnl) production in Erwinia carotovora subsp. carotovora strain 71 occurs upon DNA damage via a unique regulatory circuit involving recA, rdgA and rdgB [8].

Other interactions of rdgB

• Suppression of the defects in rdgB mutants of Escherichia coli K-12 by the cloned purA gene [7].
• Disruption of the endonuclease V gene, nfi, rescues the HAP sensitivity displayed by moa and moa rdgB mutants and reduces the level of recombination and SOS induction, but it increases the level of mutagenesis [6].

References