Pathway correcting DNA replication errors in Saccharomyces cerevisiae

• Published in: The EMBO journal 1993-04, Vol.12 (4), p.1467-1473
• Main Authors: Morrison, A, Johnson, A.L, Johnston, L.H, Sugino, A
• Format: Article
• Language: English
• Subjects: 3' to 5' exonucleases; Amino Acid Sequence; Base Sequence; Biological and medical sciences; Cell Cycle; dna modification; DNA Mutational Analysis; DNA Polymerase II - genetics; DNA Repair; DNA Replication; DNA-directed DNA polymerase; enzyme activity; errors; Exonucleases - metabolism; Fundamental and applied biological sciences. Psychology; Fungal Proteins - genetics; Gene Expression Regulation, Fungal; mismatch repair; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; mutagenesis; Mutation; nucleases; nucleotide sequences; Oligodeoxyribonucleotides - chemistry; pms1 gene; pol3 gene; Replication; RNA, Fungal - genetics; RNA, Messenger - genetics; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; structural genes; Structure-Activity Relationship
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1993.tb05790.x

Mutation of predicted 3'-5' exonuclease active site residues of Saccharomyces cerevisiae POL3 DNA polymerase or deletion of the PMS1 mismatch repair gene lead to relative (to wild type) spontaneous mutation rates of approximately 130 and 41, respectively, measured at a URA3 reporter gene inserted near to a defined replication origin. The POL3 exonuclease-deficient mutant pol3-01 generated most classes of single base mutation in URA3, indicating a broad specificity that generally corresponds to that of the PMS1 system. pol3-01 pms1 haploid cells ceased growth after a few divisions with no unique terminal cell morphology. A pol3-01/pol3-01 pms1/pms1 diploid was viable and displayed an estimated URA3 relative mutation rate of 2 X 10(4), which we calculate to be catastrophically high in a haploid. The relationship between the relative mutation rates of pol3-01 and pms1 was multiplicative, indicating action in series. The PMS1 transcript showed the same cell cycle periodicity as those of a set of DNA replication genes that includes POL3, suggesting PMS1 is co-regulated with these genes. We propose that the POL3 3' to 5' exonuclease and the PMS1 mismatch repair system act on a common pathway analogous to the dnaQ to mutHLS pathway of DNA replication error correction in Escherichia coli.