Article
- The EMBO Journal (2003) 22, 3761 - 3771
- doi:10.1093/emboj/cdg385
Subject Categories:
The 3D structure of the fusion primed Sendai F-protein determined by electron cryomicroscopy
Kai Ludwig1,3, Bolormaa Baljinnyam2,3, Andreas Herrmann2 and Christoph Böttcher1
- Forschungszentrum für Elektronenmikroskopie, Freie Universität Berlin, Berlin, Germany
- Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, Institut für Biologie/Biophysik, Berlin, Germany
- K.Ludwig and B.Baljinnyam contributed equally to this work
Correspondence to:
Andreas Herrmann, E-mail: andreas.herrmann@rz.hu-berlin.de
Received 5 December 2002; Accepted 12 June 2003; Revised 11 June 2003
Abstract
The three dimensional (3D) structure of the ectodomain of the entire fusion mediating F protein from Sendai virus [MW (trimer) 
177 kDa] has been determined by cryoelectron microscopy of single molecules and subsequent 3D reconstruction at a resolution of 16 Å. The reconstruction, which has been obtained from the native, proteolytic processed fusion primed F1+F2 form, shows the protein protruding 170 Å out of the membrane in a homotrimeric association. It consists of a defined 65 Å wide distal head and an adjacent neck, which is connected to an 70 Å elongated stalk. Although the overall shape appears to be similar to the recently reported X-ray structure of the Newcastle disease virus F protein, a closer comparison reveals structural differences suggesting that the investigated Sendai F structure represents an advanced state towards the fusion active conformation.
Keywords:
- 3D reconstruction,
- cryoelectron microscopy,
- F glycoprotein,
- Sendai virus,
- single particle analysis
