5MF1

Crystal structure of a C-terminally truncated trimeric ectodomain of the Chlamydomonas reinhardtii gamete fusion protein HAP2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.3 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.219 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The Ancient Gamete Fusogen HAP2 Is a Eukaryotic Class II Fusion Protein.

Fedry, J.Liu, Y.Pehau-Arnaudet, G.Pei, J.Li, W.Tortorici, M.A.Traincard, F.Meola, A.Bricogne, G.Grishin, N.V.Snell, W.J.Rey, F.A.Krey, T.

(2017) Cell 168: 904-915.e10

  • DOI: 10.1016/j.cell.2017.01.024

  • PubMed Abstract: 
  • Sexual reproduction is almost universal in eukaryotic life and involves the fusion of male and female haploid gametes into a diploid cell. The sperm-restricted single-pass transmembrane protein HAP2-GCS1 has been postulated to function in membrane me ...

    Sexual reproduction is almost universal in eukaryotic life and involves the fusion of male and female haploid gametes into a diploid cell. The sperm-restricted single-pass transmembrane protein HAP2-GCS1 has been postulated to function in membrane merger. Its presence in the major eukaryotic taxa-animals, plants, and protists (including important human pathogens like Plasmodium)-suggests that many eukaryotic organisms share a common gamete fusion mechanism. Here, we report combined bioinformatic, biochemical, mutational, and X-ray crystallographic studies on the unicellular alga Chlamydomonas reinhardtii HAP2 that reveal homology to class II viral membrane fusion proteins. We further show that targeting the segment corresponding to the fusion loop by mutagenesis or by antibodies blocks gamete fusion. These results demonstrate that HAP2 is the gamete fusogen and suggest a mechanism of action akin to viral fusion, indicating a way to block Plasmodium transmission and highlighting the impact of virus-cell genetic exchanges on the evolution of eukaryotic life.


    Organizational Affiliation

    Unité de Virologie Structurale, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724 Paris, France; CNRS UMR 3569, 25-28 Rue du Docteur Roux, 75724 Paris, France; Université Paris Descartes Sorbonne Paris Cité, Institut Pasteur, Rue du Docteur Roux, 75015 Paris, France; Institute of Virology, Hannover Medical School, 30625 Hannover, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fusion protein HAP2/GCS1
A, B, C
611Chlamydomonas reinhardtiiMutation(s): 0 
Gene Names: HAP2 (GCS1)
Find proteins for A4GRC6 (Chlamydomonas reinhardtii)
Go to UniProtKB:  A4GRC6
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B, C
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
NGA
Query on NGA

Download SDF File 
Download CCD File 
A, B, C
N-ACETYL-D-GALACTOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-JAJWTYFOSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.3 Å
  • R-Value Free: 0.266 
  • R-Value Work: 0.219 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 103.970α = 90.00
b = 114.060β = 90.00
c = 137.420γ = 90.00
Software Package:
Software NamePurpose
autoSHARPphasing
XSCALEdata scaling
XDSdata reduction
BUSTERrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
ERCFrance"CelCelFus"

Revision History 

  • Version 1.0: 2017-03-08
    Type: Initial release
  • Version 1.1: 2017-08-16
    Type: Data collection