Variable-temperature size exclusion chromatography for the study of the structural changes in g-quadruplex.
The conformational equilibria of a guanine-rich sequence found at the promoter region of the human c-kit oncogene are studied by means of circular dichroism spectroscopy (CD) and variable-temperature size exclusion chromatography (SEC). It is shown that the wild sequence ckit21 exists as a mixture of monomeric and multimeric G-quadruplexes. Appropriate mutation of several bases in the wild sequence produces the shift from parallel to antiparallel G-quadruplex, as well as the disappearance of multimeric species. The shift from the antiparallel to the parallel conformation induced by temperature is reflected in both CD and SEC profiles.
Solution Equilibria and Chemometrics Group (Associate Unit UB-CSIC), Department of Analytical Chemistry, University of Barcelona, Diagonal 647, 08028 Barcelona, Spain.
Sanae
S
Benabou
Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), CIBER-BBN Networking Research Centre on Bioengineering, Biomaterials and Nanomedicine, Jordi Girona 18-26, 08034 Barcelona, Spain.
Ramon
R
Eritja
Solution Equilibria and Chemometrics Group (Associate Unit UB-CSIC), Department of Analytical Chemistry, University of Barcelona, Diagonal 647, 08028 Barcelona, Spain.
Raimundo
0000-0001-8716-8356
R
Gargallo