1Z3H

The exportin Cse1 in its cargo-free, cytoplasmic state

Summary for 1Z3H

• Entry DOI: 10.2210/pdb1z3h/pdb
• Related: 1wa5
• Descriptor: Importin alpha re-exporter, MAGNESIUM ION (2 entities in total)
• Functional Keywords: cse1, exportin, nuclear transport, heat repeat, protein transport
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Cellular location: Cytoplasm: P33307
• Total number of polymer chains: 2
• Total formula weight: 221077.65

Authors

Cook, A.,Fernandez, E.,Lindner, D.,Ebert, J.,Schlenstedt, G.,Conti, E. (deposition date: 2005-03-12, release date: 2005-05-10, Last modification date: 2024-03-13)

Primary citation

Cook, A.,Fernandez, E.,Lindner, D.,Ebert, J.,Schlenstedt, G.,Conti, E.
The structure of the nuclear export receptor cse1 in its cytosolic state reveals a closed conformation incompatible with cargo binding
Mol.Cell, 18:355-367, 2005

PubMed Abstract: Cse1 mediates nuclear export of importin alpha, the nuclear localization signal (NLS) import adaptor. We report the 3.1 A resolution structure of cargo-free Cse1, representing this HEAT repeat protein in its cytosolic state. Cse1 is compact, consisting of N- and C-terminal arches that interact to form a ring. Comparison with the structure of cargo-bound Cse1 shows a major conformational change leading to opening of the structure upon cargo binding. The largest structural changes occur within a hinge region centered at HEAT repeat 8. This repeat contains a conserved insertion that connects the RanGTP and importin alpha contact sites and that is essential for binding. In the cargo-free state, the RanGTP binding sites are occluded and the importin alpha sites are distorted. Mutations that destabilize the N- to C-terminal interaction uncouple importin alpha and Ran binding, suggesting that the closed conformation prevents association with importin alpha.

PubMed: 15866177
DOI: 10.1016/j.molcel.2005.03.021

Experimental method

X-RAY DIFFRACTION (3.1 Å)