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Sequence-specific targeting and covalent modification of human genomic DNA.

ABSTRACT: We compare two techniques which enable selective, nucleotide-specific covalent modification of human genomic DNA, as assayed by quantitative ligation- mediated PCR. In the first, a purine motif triplex-forming oligonucleotide with a terminally appended chlorambucil was shown to label a target guanine residue adjacent to its binding site in 80% efficiency at 0.5 microM. Efficiency was higher in the presence of the triplex-stabilizing intercalator coralyne. In the second method, an oligonucleotide targeting a site containing all four bases and bearing chlorambucil on an interior base was shown to efficiently react with a specific nucleotide in the target sequence. The targeted sequence in these cases was in the DQbeta1*0302 allele of the MHC II locus.

SUBMITTER: Belousov ES

PROVIDER: S-EPMC146908 | biostudies-other | 1997 Sep

REPOSITORIES: biostudies-other

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Sequence-specific targeting and covalent modification of human genomic DNA.

Belousov E S ES Afonina I A IA Podyminogin M A MA Gamper H B HB Reed M W MW Wydro R M RM Meyer R B RB

Nucleic acids research 19970901 17

We compare two techniques which enable selective, nucleotide-specific covalent modification of human genomic DNA, as assayed by quantitative ligation- mediated PCR. In the first, a purine motif triplex-forming oligonucleotide with a terminally appended chlorambucil was shown to label a target guanine residue adjacent to its binding site in 80% efficiency at 0.5 microM. Efficiency was higher in the presence of the triplex-stabilizing intercalator coralyne. In the second method, an oligonucleotide ...[more]

PMID: 9254701

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