We should also
mention that vectorial transport across the NPC
does not require an asymmetric NPC with regard to
its cytoplasmic and nuclear half but rather an
asymmetric NPC near-field, for example, in the form
of a Ran gradient. Indeed, the cytoplasmic NPC near-
field is rich in Ran-GDP whereas the nuclear NPC
near-field is rich in Ran-GTP.