How Osmolytes Affect the Stability of GNRA Hairpins.

Osmolytes (small, chemically diverse, organic solutes) are an essential part of the cellular response to environmental stresses such as changes in temperature, pressure, and salinity. Although much is known about the effects of osmolytes on protein structures and nucleic acid structures, the effects of osmolytes on secondary structure motifs, is generally less-well understood. Secondary structure motifs such as non-Watson Crick base pairs, bulged and mispaired nucleotides, and the loops of nucleic acid hairpins play important functional roles as protein and drug binding sites and participants in tertiary structure contacts. To begin quantifying the effects of osmolytes on nucleic acid secondary structure motifs, we are investing the folding thermodynamics of the stable GN(R)A hairpin loops of DNA and RNA in the presence and absence of a neutral cosolute (PEG 200) using UV-Vis and Circular Dichroism spectroscopy. We will present our current findings as well proposed future directions for this work