title: Analysis of the yeast nucleoporin Nup188 reveals a conserved S-like structure with similarity to karyopherins.
abstract: Nuclear pore complexes (NPCs) embedded in the double nuclear membrane mediate the entire nucleocytoplasmic transport between the nucleus and cytoplasm. Each NPC is composed of about 30 different proteins (nucleoporins or Nups), which exist in multiple (8, 16 or 32) copies within the NPC scaffold. Recently, we have identified and characterized the large structural Nups, Nup188 and Nup192, from the thermophilic eukaryote Chaetomium thermophilum, which exhibited superior properties for biochemical and structural studies, when compared to their mesophilic orthologs. Here, we study the large structural Nups from the model organism yeast Saccharomyces cerevisiae. Our data show that yeast Nup188 like its thermophilic orthologue ctNup188 exhibits a twisted S-like structure, which flexibly binds the linker nucleoporin Nic96 via a short conserved α-helix motif. Using bioinformatic methods, we have generated a pseudo-atomic structural model of Nup188 and its related Nup192, which further strengthens the view that the large α-solenoid structural Nups are related to karyopherins.
authors.affiliation: Biochemie-Zentrum der Universität Heidelberg (BZH), Im Neuenheimer Feld 328, D-69120 Heidelberg, Germany. Dirk.Flemming@bzh.uni-heidelberg.de
authors.forename: Dirk
authors.initials: D
authors.lastname: Flemming
authors.forename: Damien P
authors.initials: DP
authors.lastname: Devos
authors.forename: Johannes
authors.initials: J
authors.lastname: Schwarz
authors.forename: Stefan
authors.initials: S
authors.lastname: Amlacher
authors.forename: Malik
authors.initials: M
authors.lastname: Lutzmann
authors.forename: Ed
authors.initials: E
authors.lastname: Hurt
mesh_terms: D002597:Chaetomium / Q000378:metabolism; D019295:Computational Biology; D007091:Image Processing, Computer-Assisted; D028884:Karyopherins / Q000737:chemistry*; D008854:Microscopy, Electron; D008958:Models, Molecular; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry*; D010957:Plasmids; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000737:chemistry*
chemical_list: D028884:Karyopherins; C100410:NUP188 protein, S cerevisiae; D028861:Nuclear Pore Complex Proteins; D029701:Saccharomyces cerevisiae Proteins