Skip to main content
Nucleic Acids Research logoLink to Nucleic Acids Research
. 1999 Feb 15;27(4):1176–1181. doi: 10.1093/nar/27.4.1176

Chromosomal mutations induced by triplex-forming oligonucleotides in mammalian cells.

K M Vasquez 1, G Wang 1, P A Havre 1, P M Glazer 1
PMCID: PMC148300  PMID: 9927753

Abstract

Specific recognition of a region of duplex DNA by triplex-forming oligonucleotides (TFOs) provides an attractive strategy for genetic manipulation. Based on this, we have investigated the ability of the triplex-directed approach to induce mutations at a chromosomal locus in living cells. A mouse fibroblast cell line was constructed containing multiple chromosomal copies of the lambdasupFG1 vector carrying the supFG1 mutation-reporter gene. Cells were treated with specific (psoAG30) or control (psoSCR30) psoralen-conjugated TFOs in the presence and absence of UVA irradiation. The results demonstrated a 6- to 10-fold induction of supFG1 mutations in the psoAG30-treated cells as compared with psoSCR30-treated or untreated control cells. Interestingly, UVA irradiation had no effect onthe mutation frequencies induced by the psoralen-conjugated TFOs, suggesting a triplex-mediated but photoproduct-independent process of mutagenesis. Sequencing data were consistent with this finding since the expected T.A-->A.T transversions at the predicted psoralen crosslinking site were not detected. However, insertions and deletions were detected within the triplex binding site, indicating a TFO-specific induction of mutagenesis. This result demonstrates the ability of triplex-forming oligonucleotides to influence mutation frequencies at a specific site in a mammalian chromosome.

Full Text

The Full Text of this article is available as a PDF (90.3 KB).


Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press

RESOURCES