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Table 7. Polymerase action on aristolochic acid-induced adducts in vitro
Test system Result Reference
Site-specifically adducted oligonucleotides containing AA-
DNA adducts were used as templates for T7 DNA polymerase
in primer extension reactions. DNA sythesis products were
analysed on polyacrylamide gels using 5′- 32 P-labelled primers
Site-specifically adducted oligonucleotides containing AA-
DNA adducts were used as templates for human DNA
polymerase α in primer extension reactions. DNA synthesis
products were analysed on polyacrylamide gels using 5′- 32 Plabelled
primers
Polymerase arrest assay was used to determine the distribution
of DNA adducts formed by AAI and AAII in vitro in the mouse
c-Ha-ras gene. Arrest spectra were obtained on sequencing gels
using 5′- 32 P-labelled primers and polymerase Sequenase
Polymerase arrest assay combined with a terminal transferasedependent
PCR (TD-PCR) was used to map the distribution of
DNA adducts formed by AAI and AAII in vitro in the human
TP53 gene of MCF-7 DNA. Adducted DNA was used as
template for TD-PCR.
Mainly block of DNA synthesis at the nucleotide 3′ to each
adduct, but translesional synthesis was also observed. dA-AAI and
dA-AAII allowed incorporation of dAMP and dTMP directly
across equally well, deoxyguanosine adducts allowed preferential
incorporation of dCMP
Mainly block of DNA synthesis at the nucleotide 3′ to adducts dA-
AAI, dG-AAI and dA-AAII. Only dG-AAII allowed substantial
translesional synthesis
AAI-induced adducts showed preference for adenine residues.
AAII-induced damage was found at guanine, adenine and cytosine
residues. Adduct distribution was not random.
AA-DNA binding spectrum in the TP53 gene: CpG sites are not
preferential targets for AAI or AAII.
Broschard
et al.
(1994)
Broschard
et al.
(1995)
Arlt et al.
(2000)
Arlt et al.
(2001b)
AA, aristolochic acids (mixed); AAI and AAII, aristolochic acids I and II; dA-AAI, 7-(deoxyadenosin-N 6 -yl)aristolactam I; dA-AAII,
7-(deoxyadenosin-N 6 -yl)aristolactam II; dG-AAI, 7-(deoxyguanosin-N 2 -yl)aristolactam I; dG-AAII, 7-(deoxyguanosin-N 2 -yl)aristolactam II;
PCR, polymerase chain reaction; dAMP, deoxyadenosine 3′-monophosphate; dTMP, deoxythymidine 3′-monophosphate; dCMP, deoxycytidine
3′-monophosphate
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IARC MONOGRAPHS VOLUME 82