Isolation of the gene encoding yeast DNA polymerase I.
A yeast genomic DNA expression library in lambda gt11 antibody prepared against yeast DNA polymerase I were used to isolate the gene encoding DNA polymerase I. The identity of the DNA polymerase I gene was determined by several criteria. First, the clone-encoded protein is immunologically related to DNA polymerase I. Second, cells containing the gene cloned in the high copy number plasmid YEp24 overproduce the polymerase activity 4- to 5-fold as measured in yeast extracts. Finally, insertion of the gene downstream from a bacteriophage T7 promoter allows synthesis of yeast DNA polymerase I in Escherichia coli. Gene disruption and Southern hybridization experiments show that the polymerase is encoded by an essential, single copy gene. Examination of the germinated spores containing the disrupted gene reveals a defect in nuclear division and a terminal phenotype typical of replication mutants.
D002453:Cell Cycle; D003001:Cloning, Molecular; D003429:Cross Reactions; D004256:DNA Polymerase I / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005796:Genes; D005800:Genes, Fungal; D005822:Genetic Vectors; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000201:enzymology / Q000235:genetics*
D004256:DNA Polymerase I