Figure 5. Summary of the charge effect on nucleocytoplasmic transport.

(A) Charge effect on passive diffusion. Small positively charged molecules (<40 kDa, red dots) permeate the NPC through the central channel just as small negatively charged (blue dots), but with a shorter and narrower route. (B) Charge effect on facilitated transport. Regardless of the cargo’s charge, transiting cargo complexes (transport receptor/cargo) follow the pathways of the transport receptor through the FG filamentous regions at the periphery around the central channel.