title: Structural insights into membrane interaction and caveolar targeting of dynamin-like EHD2.
abstract: The dynamin-related Eps15-homology domain-containing protein 2 (EHD2) is a membrane-remodeling ATPase that regulates the dynamics of caveolae. Here, we established an electron paramagnetic resonance (EPR) approach to characterize structural features of membrane-bound EHD2. We show that residues at the tip of the helical domain can insert into the membrane and may create membrane curvature by a wedging mechanism. Using EPR and X-ray crystallography, we found that the N terminus is folded into a hydrophobic pocket of the GTPase domain in solution and can be released into the membrane. Cryoelectron microscopy demonstrated that the N terminus is not essential for oligomerization of EHD2 into a membrane-anchored scaffold. Instead, we found a function of the N terminus in regulating targeting and stable association of EHD2 to caveolae. Our data uncover an unexpected, membrane-induced regulatory switch in EHD2 and demonstrate the versatility of EPR to study structure and function of dynamin superfamily proteins.
authors: Max-Delbrück-Center for Molecular Medicine, Crystallography, Robert-Rössle-Straße 10, 13092 Berlin, Germany.|Institute of Chemistry and Biochemistry, Free University Berlin, Takustraße 6, 14195 Berlin, Germany.
authors: Claudio
authors: C
authors: Shah
authors: Post Graduate Department of Physics, Rani Channamma University, Vidyasangama, Belagavi-591156, India.
authors: Balachandra G
authors: BG
authors: Hegde
authors: Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden.
authors: Björn
authors: B
authors: Morén
authors: Institute of Medical Physics and Biophysics, Charité, Charitéplatz 1, 10117 Berlin, Germany.
authors: Elmar
authors: E
authors: Behrmann
authors: Institute of Medical Physics and Biophysics, Charité, Charitéplatz 1, 10117 Berlin, Germany.|UltraStrukturNetzwerk, Max-Planck-Institute for Molecular Genetics, Ihnestraße 73, 14195 Berlin.
authors: Thorsten
authors: T
authors: Mielke
authors: Max-Delbrück-Center for Molecular Medicine, Crystallography, Robert-Rössle-Straße 10, 13092 Berlin, Germany.
authors: Gregor
authors: G
authors: Moenke
authors: Institute of Medical Physics and Biophysics, Charité, Charitéplatz 1, 10117 Berlin, Germany.
authors: Christian M T
authors: CMT
authors: Spahn
authors: Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden.
authors: Richard
authors: R
authors: Lundmark
authors: Max-Delbrück-Center for Molecular Medicine, Crystallography, Robert-Rössle-Straße 10, 13092 Berlin, Germany.|Institute of Medical Physics and Biophysics, Charité, Charitéplatz 1, 10117 Berlin, Germany.
authors: Oliver
authors: O
authors: Daumke
authors: Zilkha Neurogenetic Institute, University of Southern California, 1501 San Pablo Street, Los Angeles, CA 90033, USA.
authors: Ralf
authors: R
authors: Langen
mesh_terms: D041721:3T3-L1 Cells; D000818:Animals; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D021941:Caveolae / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D004578:Electron Spin Resonance Spectroscopy; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D017510:Protein Folding; D055550:Protein Stability; D017434:Protein Structure, Tertiary
chemical_list: D002352:Carrier Proteins; C485117:EHD2 protein, mouse; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins