title: Plasticity of an ultrafast interaction between nucleoporins and nuclear transport receptors.
abstract: The mechanisms by which intrinsically disordered proteins engage in rapid and highly selective binding is a subject of considerable interest and represents a central paradigm to nuclear pore complex (NPC) function, where nuclear transport receptors (NTRs) move through the NPC by binding disordered phenylalanine-glycine-rich nucleoporins (FG-Nups). Combining single-molecule fluorescence, molecular simulations, and nuclear magnetic resonance, we show that a rapidly fluctuating FG-Nup populates an ensemble of conformations that are prone to bind NTRs with near diffusion-limited on rates, as shown by stopped-flow kinetic measurements. This is achieved using multiple, minimalistic, low-affinity binding motifs that are in rapid exchange when engaging with the NTR, allowing the FG-Nup to maintain an unexpectedly high plasticity in its bound state. We propose that these exceptional physical characteristics enable a rapid and specific transport mechanism in the physiological context, a notion supported by single molecule in-cell assays on intact NPCs.
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany; University Grenoble Alpes, IBS, F-38044 Grenoble, France; CNRS, IBS, F-38044 Grenoble, France; CEA, IBS, F-38044 Grenoble, France.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Milles
authors.affiliation: Molecular Biomechanics group, HITS gGmbH, Schloß-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany; IWR - Interdisciplinary Center for Scientific Computing, Im Neuenheimer Feld 368, 69120, Heidelberg, Germany.
authors.forename: Davide
authors.initials: D
authors.lastname: Mercadante
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Iker Valle
authors.initials: IV
authors.lastname: Aramburu
authors.affiliation: University Grenoble Alpes, IBS, F-38044 Grenoble, France; CNRS, IBS, F-38044 Grenoble, France; CEA, IBS, F-38044 Grenoble, France.
authors.forename: Malene Ringkjøbing
authors.initials: MR
authors.lastname: Jensen
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Niccolò
authors.initials: N
authors.lastname: Banterle
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Koehler
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Swati
authors.initials: S
authors.lastname: Tyagi
authors.affiliation: Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
authors.forename: Jane
authors.initials: J
authors.lastname: Clarke
authors.affiliation: Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Shammas
authors.affiliation: University Grenoble Alpes, IBS, F-38044 Grenoble, France; CNRS, IBS, F-38044 Grenoble, France; CEA, IBS, F-38044 Grenoble, France. Electronic address: martin.blackledge@ibs.fr.
authors.forename: Martin
authors.initials: M
authors.lastname: Blackledge
authors.affiliation: Molecular Biomechanics group, HITS gGmbH, Schloß-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany; IWR - Interdisciplinary Center for Scientific Computing, Im Neuenheimer Feld 368, 69120, Heidelberg, Germany. Electronic address: frauke.graeter@h-its.org.
authors.forename: Frauke
authors.initials: F
authors.lastname: Gräter
authors.affiliation: Structural and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany. Electronic address: lemke@embl.de.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Lemke
mesh_terms: D021581:Active Transport, Cell Nucleus; D018360:Crystallography, X-Ray; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D028884:Karyopherins / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry* / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism; D012441:Saccharomyces cerevisiae
chemical_list: D028884:Karyopherins; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins