Involvement of mouse Rev3 in tolerance of endogenous and exogenous DNA damage.
The Rev3 gene of Saccharomyces cerevisiae encodes the catalytic subunit of DNA polymerase zeta that is implicated in mutagenic translesion synthesis of damaged DNA. To investigate the function of its mouse homologue, we have generated mouse embryonic stem cells and mice carrying a targeted disruption of Rev3. Although some strain-dependent variation was observed, Rev3(-/-) embryos died around midgestation, displaying retarded growth in the absence of consistent developmental abnormalities. Rev3(-/-) cell lines could not be established, indicating a cell-autonomous requirement of Rev3 for long-term viability. Histochemical analysis of Rev3(-/-) embryos did not reveal aberrant replication or cellular proliferation but demonstrated massive apoptosis in all embryonic lineages. Although increased levels of p53 are detected in Rev3(-/-) embryos, the embryonic phenotype was not rescued by the absence of p53. A significant increase in double-stranded DNA breaks as well as chromatid and chromosome aberrations was observed in cells from Rev3(-/-) embryos. The inner cell mass of cultured Rev3(-/-) blastocysts dies of a delayed apoptotic response after exposure to a low dose of N-acetoxy-2-acetylaminofluorene. These combined data are compatible with a model in which, in the absence of polymerase zeta, double-stranded DNA breaks accumulate at sites of unreplicated DNA damage, eliciting a p53-independent apoptotic response. Together, these data are consistent with involvement of polymerase zeta in translesion synthesis of endogenously and exogenously induced DNA lesions.
Van Sloun
Petra P H
PP
Department of Radiation Genetics and Chemical Mutagenesis, Leiden University Medical Center, 2300 RA Leiden, The Netherlands.
Varlet
Isabelle
I
Sonneveld
Edwin
E
Boei
Jan J W A
JJ
Romeijn
Ron J
RJ
Eeken
Jan C J
JC
De Wind
Niels
N
D000099:Acetoxyacetylaminofluorene / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis; D001755:Blastocyst / Q000187:drug effects / Q000378:metabolism; D002455:Cell Division; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D003433:Crosses, Genetic; D004249:DNA Damage; D004259:DNA-Directed DNA Polymerase; D020964:Embryo Loss; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D020287:In Situ Nick-End Labeling; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D016297:Mutagenesis, Site-Directed; D016133:Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins; D013234:Stem Cells / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; D016159:Tumor Suppressor Protein p53; D000099:Acetoxyacetylaminofluorene; D004259:DNA-Directed DNA Polymerase; C092602:REV3 protein, S cerevisiae