1. I. Protein export
II. Structure and composition of the nuclear pore complex (NPC)
III. Mechanism of translocation through the NPC

2. THE HETEROKARYON ASSAY

4. Domain Organization of Importin β
Ran-GTP
cargo
NPC

7. Structure of the exportin Cse1 with RanGTP and cargo

10. THE METAZOAN NPC

11. THE YEAST NPC
Rout et al.(2000) JCB 148:635

12. and the FG-repeats within the NPC
Interaction between nuclear transport receptors
and the FG-repeats within the NPC

13. and the FG-repeats within the NPC
Interaction between nuclear transport receptors
and the FG-repeats within the NPC

14. Organization of the NPC

15. Specificity Models of the NPC
Brownian Gate
Selective Phase
‘Oily Spaghetti

16. SUMMARY
I. Short signals target proteins into and out of the nucleus
Many proteins shuttle: regulation
II. Many transport events are mediated by the importin β
superfamily of importins and exportins
III. Directionality is conferred by nuclear RanGTP
Ran-GTP mediates substrate release (importins) or substrate
binding (exportins)
per import/export cycle ~ only one GTP is hydrolyzed
RanGTP gradient provides energy for transport
IV. NPC functions as facilitated diffusion channel
FG rich repeats provide docking sites for transport factors