When DNA molecules are heated they denature. This occurs locally so that
loops of molten single DNA strands form, connected by intact double-stranded
DNA pieces. The properties of this "melting" transition have been intensively
investigated. Recently there has been a surge of interest in this question,
caused by experiments determining the properties of partially bound DNA
confined to nanochannels. But how does such confinement affect the melting
transition? To answer this question we introduce, and solve a model predicting
how confinement affects the melting transition for a simple model system by
first disregarding the effect of self-avoidance. We find that the transition is
smoother for narrower channels. By means of Monte-Carlo simulations we then
show that a model incorporating self-avoidance shows qualitatively the same
behaviour and that the effect of confinement is stronger than in the ideal
case.Comment: 5 pages, 4 figures, supplementary materia
