Characterization of tertiary folding of RNA by circular dichroism and urea.

CD spectroscopy can be used to monitor RNA tertiary folding transitions that may not be observable by absorbance spectroscopy. With the use of computer-controlled titrators, data can be acquired rapidly, and accurate thermodynamic properties can be obtained over a wide variety of conditions. Thus, CD spectroscopy provides a useful complement to site-resolved or chemical modification methods.