STABILITY AND TRANSITION IN A DNA TETRAPLEX: A MODEL FOR TELOMERES

The theory of cooperative transition has been applied to explain the stability and melting behavior in a DNA tetraplex, which is a model for telomeres. The transition profile and heat capacity curves are best explained in terms of two variable parameters, namely nucleation and propagation parameters. The effect of strand concentration and consequent change in enthalpy is reflected in the sharpness of transition and change in nucleation parameter. The same is true for greater stabilization in the presence of K+ ions, compared with the Na+ ion. It is ascribed to dipole and dipole-induced interactions.