The stability of intramolecular DNA quadruplexes with extended loops forming inter- and intra-loop duplexes

Abstract

We have examined the formation of intramolecular quadruplex DNA structures in which the loops have been extended so as to generate short DNA duplexes. Fluorescence melting and DNase I cleavage studies show that duplexes can be formed within each loop, but that duplexes between the loops are not stable.