title: Escherichia coli radD (yejH) gene: a novel function involved in radiation resistance and double-strand break repair.
abstract: A transposon insertion screen implicated the yejH gene in the repair of ionizing radiation-induced damage. The yejH gene, which exhibits significant homology to the human transcription-coupled DNA repair gene XPB, is involved in the repair of double-strand DNA breaks. Deletion of yejH significantly sensitized cells to agents that cause double-strand breaks (ionizing radiation, UV radiation, ciprofloxacin). In addition, deletion of both yejH and radA hypersensitized the cells to ionizing radiation, UV and ciprofloxacin damage, indicating that these two genes have complementary repair functions. The ΔyejH ΔradA double deletion also showed a substantial decline in viability following an induced double-strand DNA break, of a magnitude comparable with the defect measured when the recA, recB, recG or priA genes are deleted. The ATPase activity and C-terminal zinc finger motif of yejH play an important role in its repair function, as targeted mutant alleles of yejH did not rescue sensitivity. We propose that yejH be renamed radD, reflecting its role in the DNA repair of radiation damage.
authors.affiliation: Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Stefanie H
authors.initials: SH
authors.lastname: Chen
authors.forename: Rose T
authors.initials: RT
authors.lastname: Byrne
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Wood
authors.forename: Michael M
authors.initials: MM
authors.lastname: Cox
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000483:Alleles; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D004260:DNA Repair / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005798:Genes, Bacterial; D055029:Inverted Repeat Sequences; D016415:Sequence Alignment; D017384:Sequence Deletion; D014466:Ultraviolet Rays; D016335:Zinc Fingers
chemical_list: D000900:Anti-Bacterial Agents; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C491059:RadA protein, E coli; C071446:RecG protein, E coli; D002939:Ciprofloxacin; D000251:Adenosine Triphosphatases; C000602559:YejH protein, E coli