DNA curvature plays an important role in many biological processes. To study environmentalinfluences on DNA curvature we compared the anomalous migration on polyacrylamide gels ofligation ladders of 11 specifically-designed oligonucleotides. At low temperatures (25 degreesC and below) most of the sequences exhibited a degree of anomalous migration. Increasedtemperature had a significant effect on the anomalous migration (curvature) of some sequencesbut limited effects on others; at 50 degrees C only 1 sequence migrated anomalously. Mg2+ hada strong influence on the migration of certain sequences, whilst spermine enhanced theanomalous migration of a different set of sequences. Sequences with a GGC motif exhibitedgreater curvature than predicted by the presently-used angles for the nearest-neighbour wedgemodel and are especially sensitive to Mg2+. The data have implications for models for DNAcurvature and for environmentally-sensitive DNA conformations in the regulation of geneexpression.
|Journal||Journal of Biomolecular Structure and Dynamics|
|Publication status||Published - 1999|