Electron microscopy visualization of oligonucleotide binding to duplex DNA via triplex formation.

D I Cherny; V A Malkov; A A Volodin; M D Frank-Kamenetskii

doi:10.1006/jmbi.1993.1154

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PubMed · 8464052

Electron microscopy visualization of oligonucleotide binding to duplex DNA via triplex formation.

D I Cherny·V A Malkov·A A Volodin·M D Frank-Kamenetskii

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Abstract

Using biotinylated oligonucleotides and streptavidin as a marker, we have visualized, with the help of electron microscopy, the triplex formation. We used the natural homopurine-homopyrimidine sequence from human papillomavirus 16 cloned within a plasmid. Under conditions favouring the formation of pyrimidine-purine-pyrimidine triplex the corresponding pyrimidine oligonucleotide formed a complex with the insert and this complex was detected by electron microscopy. Similarly, under conditions favouring the formation of pyrimidine-purine-purine triplex the corresponding purine oligonucleotide formed a stable complex detected by electron microscopy. In both cases the complexes we observed exhibited remarkable sequence specificity. Near 80% of DNA molecules carried the streptavidin marker in the correct position and very few cases of non-specific binding were detected. We conclude that the triplex mode of recognition may provide very efficient sequence-specific markers for electron microscopy of DNA.

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Base Sequence Binding Sites DNA Microscopy, Electron Models, Structural Molecular Sequence Data Nucleic Acid Conformation Oligodeoxyribonucleotides Structure-Activity Relationship Comparative Study Journal Article

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D I Cherny, V A Malkov, A A Volodin, M D Frank-Kamenetskii. 1993-03-20. Electron microscopy visualization of oligonucleotide binding to duplex DNA via triplex formation.. https://doi.org/10.1006/jmbi.1993.1154

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