3QNU

Crystal structure of the cytosolic domain of human atlastin-1 in complex with GDP, hexagonal form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.306 
  • R-Value Work: 0.235 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structures of the atlastin GTPase provide insight into homotypic fusion of endoplasmic reticulum membranes.

Bian, X.Klemm, R.W.Liu, T.Y.Zhang, M.Sun, S.Sui, X.Liu, X.Rapoport, T.A.Hu, J.

(2011) Proc.Natl.Acad.Sci.USA 108: 3976-3981

  • DOI: 10.1073/pnas.1101643108
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The generation of the tubular network of the endoplasmic reticulum (ER) requires homotypic membrane fusion that is mediated by the dynamin-like, membrane-bound GTPase atlastin (ATL). Here, we have determined crystal structures of the cytosolic segmen ...

    The generation of the tubular network of the endoplasmic reticulum (ER) requires homotypic membrane fusion that is mediated by the dynamin-like, membrane-bound GTPase atlastin (ATL). Here, we have determined crystal structures of the cytosolic segment of human ATL1, which give insight into the mechanism of membrane fusion. The structures reveal a GTPase domain and athree-helix bundle, connected by a linker region. One structure corresponds to a prefusion state, in which ATL molecules in apposing membranes interact through their GTPase domains to form a dimer with the nucleotides bound at the interface. The other structure corresponds to a postfusion state generated after GTP hydrolysis and phosphate release. Compared with the prefusion structure, the three-helix bundles of the two ATL molecules undergo a major conformational change relative to the GTPase domains, which could pull the membranes together. The proposed fusion mechanism is supported by biochemical experiments and fusion assays with wild-type and mutant full-length Drosophila ATL. These experiments also show that membrane fusion is facilitated by the C-terminal cytosolic tails following the two transmembrane segments. Finally, our results show that mutations in ATL1 causing hereditary spastic paraplegia compromise homotypic ER fusion.


    Organizational Affiliation

    Department of Genetics and Cell Biology, College of Life Sciences, and Tianjin Key Laboratory of Protein Sciences, Nankai University, Tianjin 300071, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Atlastin-1
A
459Homo sapiensMutation(s): 0 
Gene Names: ATL1 (GBP3, SPG3A)
EC: 3.6.5.-
Find proteins for Q8WXF7 (Homo sapiens)
Go to Gene View: ATL1
Go to UniProtKB:  Q8WXF7
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GDP
Query on GDP

Download SDF File 
Download CCD File 
A
GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.306 
  • R-Value Work: 0.235 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 144.889α = 90.00
b = 144.889β = 90.00
c = 103.694γ = 120.00
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data collection
HKL-2000data scaling
SOLVEphasing
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2011-02-09 
  • Released Date: 2011-03-02 
  • Deposition Author(s): Liu, X.

Revision History 

  • Version 1.0: 2011-03-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance