Polymer translocation through a hairy channel mimicking the inner plug of a nuclear pore complex.

Abstract

A microscopic transport model of a polymer translocating through a nuclear pore complex (NPC) is presented based on self-consistent field theory (SCFT), with the NPC and its nucleoporins mimicked by a hairy channel. Multiple cell environment effects (electrolyte effect, excluded volume effect, NPC drag effect, and hydrophobic effect) are all considered in this hairy channel model. The influence of various parameters (polymer chain length, length of NPC, strength of hydrophobic effect, and excluded volume effect) on translocation time is studied through theoretical analysis and numerical calculation. Numerical simulation results show that an area of low nucleoporin number density exists in the NPC, which facilitates the translocation of the polymer. The results also show that the translocation time curves with increasing NPC length and polymer charge number are concave. In addition, there are critical values for NPC length and polymer charge number for which the translocation time has a minimal value. The translocation time decreases with the increasing strength of the hydrophobic effect and excluded volume effect.