The 3 '-> 5 ' exonucleases of DNA polymerases delta and epsilon and the 5 '-> 3 ' exonuclease Exo1 have major roles in postreplication mutation avoidance in Saccharomyces cerevisiae

Citation
Ht. Tran et al., The 3 '-> 5 ' exonucleases of DNA polymerases delta and epsilon and the 5 '-> 3 ' exonuclease Exo1 have major roles in postreplication mutation avoidance in Saccharomyces cerevisiae, MOL CELL B, 19(3), 1999, pp. 2000-2007
Citations number
48
Categorie Soggetti
Molecular Biology & Genetics
Journal title
MOLECULAR AND CELLULAR BIOLOGY
ISSN journal
02707306 → ACNP
Volume
19
Issue
3
Year of publication
1999
Pages
2000 - 2007
Database
ISI
SICI code
0270-7306(199903)19:3<2000:T3'5'E>2.0.ZU;2-2
Abstract
Replication fidelity is controlled by DNA polymerase proofreading and postr eplication mismatch repair. We have genetically characterized the roles of the 5'-->3' Exo1 and the 3'-->5' DNA polymerase exonucleases in mismatch re pair in the yeast Saccharomyces cerevisiae by using various genetic backgro unds and highly sensitive mutation detection systems that are based on long and short homonucleotide runs. Genetic interactions were examined among DN A polymerase epsilon (pol2-4) and delta (pol3-01) mutants defective in 3'-- >5' proofreading exonuclease, mutants defective in the 5'-->3' exonuclease Exo1, and mismatch repair mutants (msh2, msh3, or msh6). These three exonuc leases play an important role in mutation avoidance. Surprisingly, the muta tion rate in an exo1 pol3-01 mutant was comparable to that in an msh2 pol3- 01 mutant, suggesting that they participate directly in postreplication mis match repair as well as in other DNA metabolic processes.