Nucleic Acids Research, 1987, Vol. 15, No. 10 4241-4255
© 1987
Articles |
-DNA-III. Characterization by high field 1H-NMR, anti-parallel self-recognition and
conformation of the unnatural hexadeoxyribonucleotides
-(d(CpApTpGpCpG) and
-d(CpGpCpApTpG).
Oligodeoxynucleotides as potential cellular probes for gene control
Laboratoire de Chimie Bio-Organique, Université des Sciences et Techniques du Languedoc UA 488 du CNRS, 34060 Montpellier, France *Department of Chemistry, University of Alberta Edmonton, Alberta T6G 2G2, Canada
Received February 11, 1987. Revised April 23, 1987. Accepted April 23, 1987.
High field 2-D-1H-NMR techniques permitted the assignment of all non-exchangeable protons of the unnatural deoxyribonucleotides
-[d(CpApTpGpCpG)] and
-[d(CpGpCpApTpG)]. 1-D and 2-D NOESY experiments show strong H6H8-H4, dipolar interactions for all nucleotides in both sequences. These data, together with COSY and J-reseolved spectra, indicate that these two
-oligomers adopt 3'-exo conformations of the sugar moieties in solution with anti conformations of the glycosyl linkages. Both 1H-NMR data, and hypochromicity comparison.of
-CATGCG and ß-CATGCG, demonstrate a higher degree of base stacking in the case of the
-sequence. The UV hyperchromicity at 260 run, and symmetry considerations in the imino proton NMR experiments reveal antiparallel self-recognition and duplex annealing at positions 14 for
-[d(CATGCG)] and positions 36 for
-[d(CGCATG)] The temperature variation of the imino proton NMR signals suggests that the hydrogen bonding in self-recognition is comparable in strength with that in a ß-DNA duplex, and NOE data are in accord with Watson-Crick rather than Hoogsteen base pairing.