Disease relevance of polA

• We have found that a temperature-sensitive mutation in the polA gene of Salmonella typhimurium strain LT2 causes precise excision of transposon Tn10 to occur at significantly increased frequencies in cells incubated at the restrictive temperature [1].
• The plasmid increased the ability of wild-type, polA, and uvrB hosts to support plaque production by UV-irradiated phage, and made strain LT2 hisG46 less sensitive to methyl methane sulfonate and to X rays and more responsive to the mutagenic effect of visible-light irradiation [2].

High impact information on polA

• The error-prone repair system encoded in the pKM101 plasmid markedly increased the frequency of total spontaneous reversion events in all genetic backgrounds except recA but did not affect the frequency of spontaneous deletion revertants in any background except polA [3].
• A derivative of the polA mutant unable to synthesize glutathione (GSH) was markedly more sensitive to acetaldehyde and propionaldehyde than was the polA mutant proficient in GSH synthesis [4].
• DNA was integrated into the S. typhimurium chromosome at aroC by transferring the vectors into S. typhimurium polA mutants and allowing homologous recombination to occur between the cloned and chromosomal aroC genes [5].
• Precise excision of Tn10 in Salmonella typhimurium: effects of mutations in the polA, dam, mutH and mutB genes and of methionine or ethionine in the plating medium [6].
• The effects of mutations in the polA and recA genes on mutagenesis by nitrosoguanidine in Salmonella typhimurium [7].

Chemical compound and disease context of polA

• Results of semi-quantitative plate tests indicated that polA and recA mutants of Salmonella typhimurium strain LT2 trpB1 might be significantly less mutable by nitrosoguanidine (MNNG) than were their repair-proficient parents strains [7].

Biological context of polA

• Effect of recA and polA mutations on gene duplication in Salmonella typhimurium [8].
• Other smaller mutator effects of the polA alleles on complex interactions between different polA alleles and different frameshift mutations, it is tentatively suggested that deletion frameshifts may arise mainly during DNA replication, while addition frameshifts may arise mainly during post-replication repair [9].

Associations of polA with chemical compounds

• Consistent with this hypothesis, the inhibitory effects of acetaldehyde and propionaldehyde on the growth of this polA mutant were demonstrated [4].
• One frameshift strain, hisC3076, also showed increased sensitivity to mutagenesis by ICR-191 when it carried either of two different polA alleles, whereas the hisD3052 and hisC207 frameshifts reduced sensitivity to mutagenesis in the presence of these alleles [9].

References