Mechanistic studies of hairpin to duplex conversion for trinucleotide repeat sequences.

ABSTRACT: The expansion of a trinucleotide repeat sequence, such as CAG/CTG, has been pinpointed as the molecular basis for a number of neurodegenerative disorders. It has been proposed that as part of the expansion process, these repetitive sequences adopt non-B conformations such as hairpins. However, the prevalence of these hairpins and their contributions to the DNA expansion have not been well defined. In this work, we utilized a molecular beacon strategy to examine the stability of the (CAG)(10) hairpin and also its behavior in the presence of the complementary (CTG)(10) hairpin. We find that the two hairpins represent kinetically trapped species that can coexist but irreversibly convert to duplex upon thermal induction. Furthermore, as monitored by fluorescence and optical analysis, modificat

SUBMITTER: Avila Figueroa A 

PROVIDER: S-EPMC2863172 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature