title: Mapping multivalency and differential affinities within large intrinsically disordered protein complexes with segmental motion analysis.
abstract: Intrinsically disordered proteins (IDPs) can bind to multiple interaction partners. Numerous binding regions in the IDP that act in concert through complex cooperative effects facilitate such interactions, but complicate studying IDP complexes. To address this challenge we developed a combined fluorescence correlation and time-resolved polarization spectroscopy approach to study the binding properties of the IDP nucleoporin153 (Nup153) to nuclear transport receptors (NTRs). The detection of segmental backbone mobility of Nup153 within the unperturbed complex provided a readout of local, region-specific binding properties that are usually masked in measurements of the whole IDP. The binding affinities of functionally and structurally diverse NTRs to distinct regions of Nup153 can differ by orders of magnitudes-a result with implications for the diversity of transport routes in nucleocytoplasmic transport.
authors.affiliation: Structural and Computational Biology Unit, EMBL, Meyerhofstrasse 1, 69117 Heidelberg (Germany).
authors.forename: Sigrid
authors.initials: S
authors.lastname: Milles
authors.forename: Edward A
authors.initials: EA
authors.lastname: Lemke
mesh_terms: D029721:Drosophila Proteins / Q000737:chemistry; D064267:Intrinsically Disordered Proteins / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D009038:Motion; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding
chemical_list: D029721:Drosophila Proteins; D064267:Intrinsically Disordered Proteins; D028861:Nuclear Pore Complex Proteins; C523209:Nup153 protein, Drosophila
keywords: FG-nucleoporin; fluorescence; intrinsically disordered proteins; ligand binding; multivalency