4C31

Nup1:Sac3:Sus1 complex

Summary for 4C31

• Entry DOI: 10.2210/pdb4c31/pdb
• Descriptor: NUCLEAR MRNA EXPORT PROTEIN SAC3, PROTEIN SUS1, NUCLEOPORIN NUP1 (3 entities in total)
• Functional Keywords: transport protein, nuclear transport, mrna export, gene expression pathway integration, nuclear pore
• Biological source: SACCHAROMYCES CEREVISIAE (BAKER'S YEAST); More
• Cellular location: Nucleus envelope: P46674; Nucleus, nucleoplasm: Q6WNK7; Nucleus, nuclear pore complex: P20676
• Total number of polymer chains: 8
• Total formula weight: 45855.74

Authors

Stewart, M.,Jani, D. (deposition date: 2013-08-21, release date: 2014-04-16, Last modification date: 2023-12-20)

Primary citation

Jani, D.,Valkov, E.,Stewart, M.
Structural Basis for Binding the Trex2 Complex to Nuclear Pores, Gal1 Localisation and Mrna Export.
Nucleic Acids Res., 42:6686-, 2014

PubMed Abstract: The conserved Sac3:Thp1:Sem1:Sus1:Cdc31 (TREX2) complex binds to nuclear pore complexes (NPCs) and, in addition to integrating mRNA nuclear export with preceding steps in the gene expression pathway, facilitates re-positioning of highly regulated actively transcribing genes (such as GAL1) to NPCs. Although TREX2 is thought to bind NPC protein Nup1, defining the precise role of this interaction has been frustrated by the complex pleiotropic phenotype exhibited by nup1Δ strains. To provide a structural framework for understanding the binding of TREX2 to NPCs and its function in the gene expression pathway, we have determined the structure of the Nup1:TREX2 interaction interface and used this information to engineer a Sac3 variant that impairs NPC binding while not compromising TREX2 assembly. This variant inhibited the NPC association of both de-repressed and activated GAL1 and also produced mRNA export and growth defects. These results indicate that the TREX2:Nup1 interaction facilitates the efficient nuclear export of bulk mRNA together with the re-positioning of GAL1 to NPCs that is required for transcriptional control that is mediated by removal of SUMO from repressors by NPC-bound Ulp1.

PubMed: 24705649
DOI: 10.1093/NAR/GKU252

Experimental method

X-RAY DIFFRACTION (3 Å)