Table 2.

Proteins related to the cNLS-mediated protein transport mechanism

Component	Other names	Function
Importin α	Karyopherin α	Adaptor that links cNLS-cargo to importin β1
Importin β	Karyopherin β	Transport factor that carries the cargo protein through the NPC
Ran	Gsp1*	Ras-superfamily GTPase that coordinates protein–protein interactions
CAS	Cse1*	A nuclear export factor dependent on importin α
RanGAP	Ran1*	GTPase-activating protein
RanGEF	RCC1	Guanine nucleotide exchange factor
Nup50	NPap60	Acts as a molecular ratchet that prevents futile cycles

^*in Saccharomyces cerevisiae. NLS nuclear localization signal, NPC nuclear pore complex