Fluidification of entanglements by a DNA bending protein

Abstract

In spite of the nanoscale insights into how nucleoid associated proteins (NAPs) interact with DNA in vitro, their role in modulating the mesoscale viscoelasticity of entangled cellular environments is not understood. By combining microrheology and molecular dynamics simulation we find that IHF -an abundant NAP -lowers the viscosity of entangled λDNA 20-fold at physiological stoichiometries. In turn, we expect that IHF may reduce the effective viscosity of the nucleoid ∼200-fold, suggesting a key role of DNA organisation in vivo as a genomic fluidiser.