Alkylpurine-DNA-N-glycosylase knockout mice show increased susceptibility to induction of mutations by methyl methanesulfonate.

2.50
Hdl Handle:
http://hdl.handle.net/10541/93018
Title:
Alkylpurine-DNA-N-glycosylase knockout mice show increased susceptibility to induction of mutations by methyl methanesulfonate.
Authors:
Elder, Rhoderick H; Jansen, J G; Weeks, Robert J; Willington, Mark; Deans, Bryan; Watson, Amanda J; Mynett, Kurt J; Bailey, John; Cooper, Donald P; Rafferty, Joseph A; Heeran, Mel C; Wijnhoven, S W; Van Zeeland, A A; Margison, Geoffrey P
Abstract:
Alkylpurine-DNA-N-glycosylase (APNG) null mice have been generated by homologous recombination in embryonic stem cells. The null status of the animals was confirmed at the mRNA level by reverse transcription-PCR and by the inability of cell extracts of tissues from the knockout (ko) animals to release 3-methyladenine (3-meA) or 7-methylguanine (7-meG) from 3H-methylated calf thymus DNA in vitro. Following treatment with DNA-methylating agents, increased persistence of 7-meG was found in liver sections of APNG ko mice in comparison with wild-type (wt) mice, demonstrating an in vivo phenotype for the APNG null animals. Unlike other null mutants of the base excision repair pathway, the APNG ko mice exhibit a very mild phenotype, show no outward abnormalities, are fertile, and have an apparently normal life span. Neither a difference in the number of leukocytes in peripheral blood nor a difference in the number of bone marrow polychromatic erythrocytes was found when ko and wt mice were exposed to methylating or chloroethylating agents. These agents also showed similar growth-inhibitory effects in primary embryonic fibroblasts isolated from ko and wt mice. However, treatment with methyl methanesulfonate resulted in three- to fourfold more hprt mutations in splenic T lymphocytes from APNG ko mice than in those from wt mice. These mutations were predominantly single-base-pair changes; in the ko mice, they consisted primarily of AT-->TA and GC-->TA transversions, which most likely are caused by 3-meA and 3- or 7-meG, respectively. These results clearly show an important role for APNG in attenuating the mutagenic effects of N-alkylpurines in vivo.
Affiliation:
CRC Section of Genome Damage and Repair, Paterson Institute for Cancer Research, Christie Hospital (NHS) Trust, Manchester M20 4BX, United Kingdom. RElder@picr.man.ac.uk
Citation:
Alkylpurine-DNA-N-glycosylase knockout mice show increased susceptibility to induction of mutations by methyl methanesulfonate. 1998, 18 (10):5828-37 Mol. Cell. Biol.
Journal:
Molecular and Cellular Biology
Issue Date:
Oct-1998
URI:
http://hdl.handle.net/10541/93018
PubMed ID:
9742100
Type:
Article
Language:
en
ISSN:
0270-7306
Appears in Collections:
All Paterson Institute for Cancer Research

Full metadata record

DC FieldValue Language
dc.contributor.authorElder, Rhoderick Hen
dc.contributor.authorJansen, J Gen
dc.contributor.authorWeeks, Robert Jen
dc.contributor.authorWillington, Marken
dc.contributor.authorDeans, Bryanen
dc.contributor.authorWatson, Amanda Jen
dc.contributor.authorMynett, Kurt Jen
dc.contributor.authorBailey, Johnen
dc.contributor.authorCooper, Donald Pen
dc.contributor.authorRafferty, Joseph Aen
dc.contributor.authorHeeran, Mel Cen
dc.contributor.authorWijnhoven, S Wen
dc.contributor.authorVan Zeeland, A Aen
dc.contributor.authorMargison, Geoffrey Pen
dc.date.accessioned2010-02-25T10:52:41Z-
dc.date.available2010-02-25T10:52:41Z-
dc.date.issued1998-10-
dc.identifier.citationAlkylpurine-DNA-N-glycosylase knockout mice show increased susceptibility to induction of mutations by methyl methanesulfonate. 1998, 18 (10):5828-37 Mol. Cell. Biol.en
dc.identifier.issn0270-7306-
dc.identifier.pmid9742100-
dc.identifier.urihttp://hdl.handle.net/10541/93018-
dc.description.abstractAlkylpurine-DNA-N-glycosylase (APNG) null mice have been generated by homologous recombination in embryonic stem cells. The null status of the animals was confirmed at the mRNA level by reverse transcription-PCR and by the inability of cell extracts of tissues from the knockout (ko) animals to release 3-methyladenine (3-meA) or 7-methylguanine (7-meG) from 3H-methylated calf thymus DNA in vitro. Following treatment with DNA-methylating agents, increased persistence of 7-meG was found in liver sections of APNG ko mice in comparison with wild-type (wt) mice, demonstrating an in vivo phenotype for the APNG null animals. Unlike other null mutants of the base excision repair pathway, the APNG ko mice exhibit a very mild phenotype, show no outward abnormalities, are fertile, and have an apparently normal life span. Neither a difference in the number of leukocytes in peripheral blood nor a difference in the number of bone marrow polychromatic erythrocytes was found when ko and wt mice were exposed to methylating or chloroethylating agents. These agents also showed similar growth-inhibitory effects in primary embryonic fibroblasts isolated from ko and wt mice. However, treatment with methyl methanesulfonate resulted in three- to fourfold more hprt mutations in splenic T lymphocytes from APNG ko mice than in those from wt mice. These mutations were predominantly single-base-pair changes; in the ko mice, they consisted primarily of AT-->TA and GC-->TA transversions, which most likely are caused by 3-meA and 3- or 7-meG, respectively. These results clearly show an important role for APNG in attenuating the mutagenic effects of N-alkylpurines in vivo.en
dc.language.isoenen
dc.subject.meshAnimals-
dc.subject.meshBone Marrow Cells-
dc.subject.meshCells, Cultured-
dc.subject.meshDNA Glycosylases-
dc.subject.meshDacarbazine-
dc.subject.meshErythrocytes-
dc.subject.meshEthylnitrosourea-
dc.subject.meshFemale-
dc.subject.meshFibroblasts-
dc.subject.meshGuanine-
dc.subject.meshHypoxanthine Phosphoribosyltransferase-
dc.subject.meshLeukocyte Count-
dc.subject.meshLiver-
dc.subject.meshMale-
dc.subject.meshMethyl Methanesulfonate-
dc.subject.meshMice-
dc.subject.meshMice, Inbred C57BL-
dc.subject.meshMice, Inbred DBA-
dc.subject.meshMice, Knockout-
dc.subject.meshMutagens-
dc.subject.meshMutation-
dc.subject.meshN-Glycosyl Hydrolases-
dc.titleAlkylpurine-DNA-N-glycosylase knockout mice show increased susceptibility to induction of mutations by methyl methanesulfonate.en
dc.typeArticleen
dc.contributor.departmentCRC Section of Genome Damage and Repair, Paterson Institute for Cancer Research, Christie Hospital (NHS) Trust, Manchester M20 4BX, United Kingdom. RElder@picr.man.ac.uken
dc.identifier.journalMolecular and Cellular Biologyen
All Items in Christie are protected by copyright, with all rights reserved, unless otherwise indicated.