Transport kinetics and physical dimension of transport routes for passive and facilitated nucleocytoplasmic transport.

A detailed description of determination of molecular size and dimension of transport routes are included in “Methods and Materials”. Particularly, to experimentally test whether the surface charge of GFP alters its hydrodynamic size, we have determined the size of −30GFP, −7GFP, +36GFP in solution by dynamic light scattering (*). GFP complex refers the complex of NLS-GFP/Imp α/Imp β1; rpL23 complex means the complex of rpL23/Imp β1; MW, molecular weight; Dm, diameter of protein candidate; Dp and Lp, effective diameter and length of the axial central channel; τ, measured transport time; CN, import events from cytoplasm to nucleus; NC, export events from nucleus to cytoplasm; E, transport efficiency; B, pore binding frequency.