2XWU

CRYSTAL STRUCTURE OF IMPORTIN 13 - UBC9 COMPLEX

Summary for 2XWU

• Entry DOI: 10.2210/pdb2xwu/pdb
• Related: 1A3S 1KPS 1Z5S 2GRN 2GRO 2GRP 2GRQ 2GRR 2X19
• Descriptor: SUMO-CONJUGATING ENZYME UBC9, IMPORTIN13 (3 entities in total)
• Functional Keywords: ligase-nuclear protein complex, nuclear import, ligase/nuclear protein
• Biological source: HOMO SAPIENS (HUMAN); More
• Cellular location: Nucleus: P63279; Cytoplasm: O94829
• Total number of polymer chains: 2
• Total formula weight: 126324.53

Authors

Gruenwald, M.,Bono, F. (deposition date: 2010-11-05, release date: 2010-12-29, Last modification date: 2023-12-20)

Primary citation

Gruenwald, M.,Bono, F.
Structure of Importin13-Ubc9 Complex: Nuclear Import and Release of a Key Regulator of Sumoylation.
Embo J., 30:427-, 2011

PubMed Abstract: Importin13 (Imp13) is an unusual β-karyopherin that is able to both import and export cargoes in and out of the nucleus. In the cytoplasm, Imp13 associates with different cargoes such as Mago-Y14 and Ubc9, and facilitates their import into the nucleus where RanGTP binding promotes the release of the cargo. In this study, we present the 2.8 Å resolution crystal structure of Imp13 in complex with the SUMO E2-conjugating enzyme, Ubc9. The structure shows an uncommon mode of cargo-karyopherin recognition with Ubc9 binding at the N-terminal portion of Imp13, occupying the entire RanGTP-binding site. Comparison of the Imp13-Ubc9 complex with Imp13-Mago-Y14 shows the remarkable plasticity of Imp13, whose conformation changes from a closed ring to an open superhelix when bound to the two different cargoes. The structure also shows that the binding mode is compatible with the sumoylated states of Ubc9. Indeed, we find that Imp13 is able to bind sumoylated Ubc9 in vitro and suppresses autosumoylation activity in the complex.

PubMed: 21139563
DOI: 10.1038/EMBOJ.2010.320

Experimental method

X-RAY DIFFRACTION (2.8 Å)