Possibility to deliver the actinomycins to DNA by hairpin oligonucleotides and caffeine clusters

 

M.A. Bitehtina, I.V. Savintsev, A.E. Kovalev, N.L.Vekshin

Institute of Cell Biophysics, Pushchino, Moscow region, 142290, Russia

 

Complexes of actinomycin D (AMD) and 7-amino-actinomycin D (7AAMD) with model hairpin oligonucleotide HP1, caffeine clusters and various types of DNA in aqueous solutions were investigated by steady-state and stopped-flow fluorimetry. Prompt non-stacking binding of actinomycins inside HP1 was observed. Strong competition between AMD and 7AAMD for a cavity in HP1 was observed. Decrease in the 7AAMD emission after addition of DNA to the 7AAMD/HP1 complex indicates that actinomycins can be redistributed from HP1 to DNA, i.e. hairpin oligonucleotides can serve as the best carriers of actinomycins.