Structural highlights
Function
[GSP1_YEAST] GTP-binding protein involved in nucleocytoplasmic transport. Required for the import of protein into the nucleus and also for RNA export. Essential for cell viability. By analogy with Ras, Ran may be activated when GTP is exchanged for bound GDP by RCC1 and inactivated when GTP is hydrolyzed by Ran upon activation by RanGAP1. [XPO1_YEAST] Receptor for the leucine-rich nuclear export signal (NES). [YRB1_YEAST] Important for the export of protein containing nuclear export signal (NES) out of the nucleus. Stimulates the GTPase activity of GSP1 and GSP2.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The karyopherin CRM1 mediates nuclear export of proteins and ribonucleoproteins bearing a leucine-rich nuclear export signal (NES). To elucidate the precise mechanism by which NES-cargos are dissociated from CRM1 in the cytoplasm, which is important for transport directionality, we determined a 2.0-A resolution crystal structure of yeast CRM1:RanBP1:RanGTP complex, an intermediate in the disassembly of the CRM1 nuclear export complex. The structure shows that on association of Ran-binding domain (RanBD) of RanBP1 with CRM1:NES-cargo:RanGTP complex, RanBD and the C-terminal acidic tail of Ran induce a large movement of the intra-HEAT9 loop of CRM1. The loop moves to the CRM1 inner surface immediately behind the NES-binding site and causes conformational rearrangements in HEAT repeats 11 and 12 so that the hydrophobic NES-binding cleft on the CRM1 outer surface closes, squeezing out the NES-cargo. This allosteric mechanism accelerates dissociation of NES by over two orders of magnitude. Structure-based mutagenesis indicated that the HEAT9 loop also functions as an allosteric autoinhibitor to stabilize CRM1 in a conformation that is unable to bind NES-cargo in the absence of RanGTP.
An allosteric mechanism to displace nuclear export cargo from CRM1 and RanGTP by RanBP1.,Koyama M, Matsuura Y EMBO J. 2010 Jun 16;29(12):2002-13. Epub 2010 May 18. PMID:20485264[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Koyama M, Matsuura Y. An allosteric mechanism to displace nuclear export cargo from CRM1 and RanGTP by RanBP1. EMBO J. 2010 Jun 16;29(12):2002-13. Epub 2010 May 18. PMID:20485264 doi:10.1038/emboj.2010.89
