TY - JOUR
T1 - Monitoring the temperature unfolding of G-quadruplexes by UV and circular dichroism spectroscopies and calorimetry techniques.
AU - Olsen, Chris M.
AU - Marky, Luis A.
PY - 2010
Y1 - 2010
N2 - DNA oligonucleotides containing guanine repeat sequences can adopt G-quadruplex (GQ) structures in the presence of specific metal ions. We report on how to use a combination of spectroscopic and calorimetric techniques to determine the spectral characteristics and thermodynamic parameters for the temperature-unfolding of GQs. Specifically, we investigated the unfolding of d(G(2)T(2)G(2)TGTG(2)T(2)G(2)), G2, and d(G(3)T(2)G(3)TGTG(3)T(2)G(3)), G3 by a combination of UV and circular dichroism (CD) spectroscopies, and differential scanning calorimetry (DSC).Analysis of the UV and CD spectra of these GQs at low (100% helix) and high (100% random coil) temperatures yielded the optimal wavelengths to determine the melting curves. In addition, the CD spectra yielded the particular conformation(s) that each GQ adopted at low temperature. DSC curves yielded complete thermodynamic profiles for the unfolding of each GQ. We use these profiles to determine the thermodynamic contributions for the formation of a G-quartet stack.
AB - DNA oligonucleotides containing guanine repeat sequences can adopt G-quadruplex (GQ) structures in the presence of specific metal ions. We report on how to use a combination of spectroscopic and calorimetric techniques to determine the spectral characteristics and thermodynamic parameters for the temperature-unfolding of GQs. Specifically, we investigated the unfolding of d(G(2)T(2)G(2)TGTG(2)T(2)G(2)), G2, and d(G(3)T(2)G(3)TGTG(3)T(2)G(3)), G3 by a combination of UV and circular dichroism (CD) spectroscopies, and differential scanning calorimetry (DSC).Analysis of the UV and CD spectra of these GQs at low (100% helix) and high (100% random coil) temperatures yielded the optimal wavelengths to determine the melting curves. In addition, the CD spectra yielded the particular conformation(s) that each GQ adopted at low temperature. DSC curves yielded complete thermodynamic profiles for the unfolding of each GQ. We use these profiles to determine the thermodynamic contributions for the formation of a G-quartet stack.
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U2 - 10.1007/978-1-59745-363-9_10
DO - 10.1007/978-1-59745-363-9_10
M3 - Article
C2 - 20012421
AN - SCOPUS:77449125296
SN - 1064-3745
VL - 608
SP - 147
EP - 158
JO - Methods in molecular biology (Clifton, N.J.)
JF - Methods in molecular biology (Clifton, N.J.)
ER -