Bending short DNAs as transversely isotropic rings in series

Despite the significance of the high flexibility exhibited by short DNAs, there remains an incomplete understanding of their anomalous persistence length. In this study, we propose to model each basic unit of gene sequences within short DNAs as a transversely isotropic ring. Our comprehensive model analysis successfully replicates the observed high flexibility of short DNAs and also displays the impact of sequence dependence, aligning with experimental findings. Furthermore, our analysis suggests that the bending behavior of short DNAs can be effectively described by the Timoshenko beam theory with the consideration of shear.