Spool-nematic ordering of dsDNA and dsRNA under confinement

Abstract

The ability of double-stranded DNA or RNA to locally melt and form kinks leads to strong non-linear elasticity effects that qualitatively affect their packing in confined spaces. Using analytical theory and numerical simulation we show that kink formation entails a mixed spool-nematic ordering of double-stranded DNA or RNA in spherical capsids, consisting of an outer spool domain and an inner, twisted nematic domain. These findings explain the experimentally observed nematic domains in viral capsids and imply that non-linear elasticity must be considered to predict the configurations and dynamics of double-stranded genomes in viruses, bacterial nucleoids or gene-delivery vehicles. The non-linear elastic theory suggests that spool-nematic ordering is a general feature of strongly confined kinkable polymers.

arXiv comment6 pages

References in corpus (7)

• Exact theory of kinkable elastic polymers
• Size, shape, and flexibility of RNA structures
• From toroidal to rod-like condensates of semiflexible polymers
• Spontaneous Domain Formation in Spherically-Confined Elastic Filaments
• Filling the void in confined polymer nematics: phase transitions in a minimal model of dsDNA packing
• Consequences of local inter-strand dehybridization for large-amplitude bending fluctuations of double-stranded DNA
• Packaging stiff polymers in small containers: A molecular dynamics study