The DNA polymerase domain of pol(epsilon) is required for rapid, efficient, and highly accurate chromosomal DNA replication, telomere length maintenance, and normal cell senescence in Saccharomyces cerevisiae.
Saccharomyces cerevisiae POL2 encodes the catalytic subunit of DNA polymerase epsilon. This study investigates the cellular functions performed by the polymerase domain of Pol2p and its role in DNA metabolism. The pol2-16 mutation has a deletion in the catalytic domain of DNA polymerase epsilon that eliminates its polymerase and exonuclease activities. It is a viable mutant, which displays temperature sensitivity for growth and a defect in elongation step of chromosomal DNA replication even at permissive temperatures. This mutation is synthetic lethal in combination with temperature-sensitive mutants or the 3'- to 5'-exonuclease-deficient mutant of DNA polymerase delta in a haploid cell. These results suggest that the catalytic activity of DNA polymerase epsilon participates in the same pathway as DNA polymerase delta, and this is consistent with the observation that DNA polymerases delta and epsilon colocalize in some punctate foci on yeast chromatids during S phase. The pol2-16 mutant senesces more rapidly than wild type strain and also has shorter telomeres. These results indicate that the DNA polymerase domain of Pol2p is required for rapid, efficient, and highly accurate chromosomal DNA replication in yeast.
Ohya
Tomoko
T
Department of Biochemistry and Molecular Biology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
Kawasaki
Yasuo
Y
Hiraga
Shin-Ichiro
S
Kanbara
Sakie
S
Nakajo
Kou
K
Nakashima
Naomi
N
Suzuki
Akiko
A
Sugino
Akio
A
D001483:Base Sequence; D020134:Catalytic Domain; D016922:Cellular Senescence; D004257:DNA Polymerase II / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers; D004261:DNA Replication; D004171:Diploidy; D007700:Kinetics; D009154:Mutation; D021122:Protein Subunits; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D017384:Sequence Deletion; D016615:Telomere / Q000235:genetics* / Q000648:ultrastructure; D013696:Temperature
D017931:DNA Primers; D021122:Protein Subunits; D004257:DNA Polymerase II