Actinomycin D facilitates transition of AT domains in molecules of sequence (aT)NAGCT(AT)n to a DNAse I detectable alternating structure

Michael J. Lane, Steven Laplante, Robert P. Rehfuss, Philip N. Borer, Charles R. Cantor

Research output: Contribution to journalArticle

15 Scopus citations


The interaction of actinomycin D with (AT)nAGCT(AT)n (where n=2,3, or 4) was investigated using a combination of imino proton NMR and DNAse I digestion. The stoichioraetry of the interaction appears to be one:one with the actinomycin chromophore intercalated between the two GC base pairs. This binding event facilitates the conversion of the flanking repetitive AT regions to an alternating conformation characterized by induced sensitivity of the ApT sequences to attack by DNAse I. The neighboring TpA sequences do not exhibit rate changes as a function of binding of the drug. The potential relevance of such ligand induced DNA structural alterations is discussed.

Original languageEnglish (US)
Pages (from-to)839-852
Number of pages14
JournalNucleic acids research
Issue number2
StatePublished - Jan 26 1987


ASJC Scopus subject areas

  • Genetics

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