A recently obtained method of relating
explicit solutions to the equations governing equilibrium configurations in the
elastic rod model of duplex DNA will be used to develop a new procedure for
calculation of configurations showing points of self-contact with non-negligible
contact forces. The procedure, which employs explicit solutions to calculate the
tertiary structures of otherwise free segments of DNA bounded by points of
self-contact, will be applied to the theories of (I) supercoiling of DNA
plasmids and (ii) the influence of histone octamers on the writhe and twist of
DNA plasmids in chromatin reconstitution, with emphasis on mononucleosomes
formed from DNA minicircles. In both cases the use of explicit solutions
facilitates analysis of the dependence of the writhe Wr and the
elastic energy E of the plasmid on the linking difference
DeltaLk. |
