PDBsum entry 1m11

Virus/receptor

PDB id: 1m11

Contents

Protein chains

243 a.a.*

278 a.a.*

254 a.a.*

238 a.a.*

* C-alpha coords only

References listed in PDB file

Key reference

Title

Structure of decay-Accelerating factor bound to echovirus 7: a virus-Receptor complex.

Authors

Y.He, F.Lin, P.R.Chipman, C.M.Bator, T.S.Baker, M.Shoham, R.J.Kuhn, M.E.Medof, M.G.Rossmann.

Ref.

Proc Natl Acad Sci U S A, 2002, 99, 10325-10329. [DOI no: 10.1073/pnas.152161599]

PubMed id

12119400

Abstract

Echoviruses are enteroviruses that belong to Picornaviridae. Many echoviruses use decay-accelerating factor (DAF) as their cellular receptor. DAF is a glycosylphosphatidyl inositol-anchored complement regulatory protein found on most cell surfaces. It functions to protect cells from complement attack. The cryo-electron microscopy reconstructions of echovirus 7 complexed with DAF show that the DAF-binding regions are located close to the icosahedral twofold axes, in contrast to other enterovirus complexes where the viral canyon is the receptor binding site. This novel receptor binding position suggests that DAF is important for the attachment of viral particles to host cells, but probably not for initiating viral uncoating, as is the case with canyon-binding receptors. Thus, a different cell entry mechanism must be used for enteroviruses that bind DAF.

Figure 1.
Fig 1. Diagrammatic structure of DAF. The green ellipses represent the SCR domains. The yellow spheres are O-linked and the orange spheres are N-linked carbohydrate moieties. GPI, glycosylphosphatidylinositol.

Figure 2.
Fig 2. Surface representation of cryoEM image reconstructions. Comparison of ECHO7 (c) with complexes of ECHO7 and DAF fragments shows (in red) the density attributed to DAF. An icosahedral asymmetric unit is outlined in black in c. Comparisons of the reconstruction of ECHO7 complexed with either DAF1234 (a) or DAF234 (b) shows that SCR domain 1 is located near the threefold axes. The surface contour is at 1 for each complex.