title: Protein interfaces of the conserved Nup84 complex from Chaetomium thermophilum shown by crosslinking mass spectrometry and electron microscopy.
abstract: A key building block of the nuclear pore complex (NPC) is the Nup84 subcomplex that has been structurally analyzed predominantly in the yeast system. To expand this analysis and gain insight into the evolutionary conservation of its structure, we reconstituted an octameric Nup84 complex using the subunits from a thermophile, Chaetomium thermophilum (ct). This assembly carries Nup37 and Elys, which are characteristic subunits of the orthologous human Nup107-Nup160 complex but absent from the yeast Saccharomyces cerevisiae. We found that Elys binds cooperatively to the complex requiring both Nup37 and Nup120. Unexpectedly, the reconstituted ctNup84 complex formed a striking dimer structure with an unpredicted side-to-side arrangement of two molecules. Finally, crosslinking mass spectrometry allowed the mapping of key protein interfaces within the Y-shaped complex. Thus, the thermophilic Nup84 complex can serve as a structural model for higher eukaryotic Nup107-Nup160 assemblies to gain insight into its possible configuration within the NPC scaffold.
authors: Biochemie-Zentrum der Universität Heidelberg, INF328, D-69120 Heidelberg, Germany.
authors: Karsten
authors: K
authors: Thierbach
authors: Alexander
authors: A
authors: von Appen
authors: Matthias
authors: M
authors: Thoms
authors: Martin
authors: M
authors: Beck
authors: Dirk
authors: D
authors: Flemming
authors: Ed
authors: E
authors: Hurt
mesh_terms: D002597:Chaetomium; D003432:Cross-Linking Reagents / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry* / Q000648:ultrastructure; D013058:Mass Spectrometry; D008854:Microscopy, Electron; D008958:Models, Molecular; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry* / Q000648:ultrastructure; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000737:chemistry*; D040681:Structural Homology, Protein; D013388:Succinimides / Q000737:chemistry
chemical_list: D003432:Cross-Linking Reagents; D005656:Fungal Proteins; D028861:Nuclear Pore Complex Proteins; D021122:Protein Subunits; D013388:Succinimides; C019358:disuccinimidyl suberate