How does the periodicity associated with nucleosomal DNA reflect on its intrinsic curvature?

Understanding signals that determine the positioning of nucleosomes along the genomic DNA is fundamental to comprehending gene regulation. Sequence dependent structural properties of DNA, like curvature and flexibility are important in DNA-protein interaction and have been shown to play an important role in nucleosome positioning. The preference of nucleosomes for specific sequences delineates the potential of those sequences to be intrinsically curved. Using theoretical models for determining the DNA curvature I have analyzed the 146 base nucleosome core DNA sequences from C. elegans. The analysis reveals a wide distribution of the molecular bend locus over the nucleosome core region. The results obtained using the theoretical model reveal that the nucleosomal DNA sequences have different degrees of curvature over the entire core region. The molecular bend loci associated with these sequences are delocalized and reflects a complex deviation of the DNA axis.