Integrative dynamic structural biology unveils conformers essential for the oligomerization of a large GTPase
- Heinrich Heine University Düsseldorf, Germany
- Ruhr University Bochum, Germany
- Forschungszentrum Jülich, Germany
- Institut Laue-Langevin, France
- University of Osnabrück, Germany
Abstract
Guanylate binding proteins (GBPs) are soluble dynamin-like proteins. They undergo a conformational transition for GTP-controlled oligomerization and disrupt membranes of intra-cellular parasites to exert their function as part of the innate immune system of mammalian cells. We apply neutron spin echo, X-ray scattering, fluorescence, and EPR spectroscopy as techniques for integrative dynamic structural biology to study the structural basis and mechanism conformational transitions in the human GBP1 (hGBP1). We mapped hGBP1’s essential dynamics from nanoseconds to milliseconds by motional spectra of sub-domains. We find a GTP-independent flexibility of the C-terminal effector domain in the μs-regime and resolve structures of two distinct conformers essential for an opening of hGBP1 like a pocketknife and oligomerization. Our results show that an intrinsic flexibility, a GTP-triggered association of the GTPase-domains, and the assembly-dependent GTP-hydrolysis are functional design principles that control hGBP1’s reversible oligomerization.
Data availability
Data availabilityThe following material is available at Zenodo in two locations: Experimental data (doi 10.5281/zenodo.6534557): (i) fluorescence decays recorded by eTCSPC used to compute the distance restraints in Supp. Tab. 3A, (ii) single-molecule multiparameter fluorescence data: all raw data, burst selection and calibration measurements, fFCS (filters and generated correlation curves) (iii) double electron-electron resonance (DEER) EPR data used for structural modeling, (iv) neutron spin-echo data and SAXS structure factor of hGBP1. Scripts for structural modeling of conformational ensembles through integrative/hybrid methods using FRET, DEER and SAXS together with the initial and selected structural ensembles (10.5281/zenodo.6565895). The experimental SAXS data and the ab initio analysis thereof are available in the SASBDB (ID SASDDD6). Structure models of hGBP1 based on experimental restraints were deposited to PDB-Dev (PDB-Dev ID: PDBDEV_00000088) using the FLR-dictionary extension (developed by PDB and the Seidel group) available on the IHM working group GitHub site (https://github.com/ihmwg/FLR-dictionary). Further data sets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.Code availabilityMost general custom-made software is directly available from http://www.mpc.hhu.de/en/software. General algorithms and source code are published under https://github.com/Fluorescence-Tools. Additional computer code custom-made for this publication is available upon request from the corresponding authors.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (EXC 2033 - 390677874 - RESOLV)
- Christian Herrmann
Deutsche Forschungsgemeinschaft (HE 2679/6-1)
- Christian Herrmann
Deutsche Forschungsgemeinschaft (SE 1195/17-1)
- Claus AM Seidel
Deutsche Forschungsgemeinschaft (STA 1325/2-1)
- Andreas M Stadler
Deutsche Forschungsgemeinschaft (KL2077/1-2)
- Johann P Klare
European Research Council (Advanced Grant 2014 hybridFRET (671208))
- Claus AM Seidel
Deutsche Forschungsgemeinschaft (project no. 267205415 / CRC 1208,subproject A03)
- Holger Gohlke
Heinrich-Heine-Universität Düsseldorf (Zentrum für Informations- und Medientechnologie (ZIM)")
- Holger Gohlke
Jülich Supercomputing Centre, Forschungszentrum Jülich (user ID: HKF7,VSK33)
- Holger Gohlke
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Peulen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Integrative dynamic structural biology unveils conformers essential for the oligomerization of a large GTPase
eLife 12:e79565.
https://doi.org/10.7554/eLife.79565
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