 |
PDBsum entry 1z4x
|
|
|
|
References listed in PDB file
|
 |
|
Key reference
|
|
|
Title
|
|
Structural studies of the parainfluenza virus 5 hemagglutinin-Neuraminidase tetramer in complex with its receptor, Sialyllactose.
|
|
|
Authors
|
|
P.Yuan,
T.B.Thompson,
B.A.Wurzburg,
R.G.Paterson,
R.A.Lamb,
T.S.Jardetzky.
|
|
|
Ref.
|
|
Structure, 2005,
13,
803-815.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
The paramyxovirus hemagglutinin-neuraminidase (HN) functions in virus attachment
to cells, cleavage of sialic acid from oligosaccharides, and stimulating
membrane fusion during virus entry into cells. The structural basis for these
diverse functions remains to be fully understood. We report the crystal
structures of the parainfluenza virus 5 (SV5) HN and its complexes with sialic
acid, the inhibitor DANA, and the receptor sialyllactose. SV5 HN shares common
structural features with HN of Newcastle disease virus (NDV) and human
parainfluenza 3 (HPIV3), but unlike the previously determined HN structures, the
SV5 HN forms a tetramer in solution, which is thought to be the physiological
oligomer. The sialyllactose complex reveals intact receptor within the active
site, but no major conformational changes in the protein. The SV5 HN structures
do not support previously proposed models for HN action in membrane fusion and
suggest alternative mechanisms by which HN may promote virus entry into cells.
|
|
|
|
|
|
Figure 7.
Figure 7. SV5 HN Tetramers
Active sites are marked by
space-filling representations of the ligand sialyllactose. The
four subunits are shown in different colors.
(A) Top view
of the SV5 HN tetramer arrangement.
(B) Side view of the
SV5 HN tetramer arrangement, with a 60° packing angle between
dimers.
(C) Side view of the superimposed SV5 HN and NDV HN
tetramers, showing a shift in dimer packing. SV5 HN is colored
blue, and NDV HN is colored green.
(D) A model for HN
tetramer rearrangement upon cell-surface receptor binding. The
HN tetramer is primarily stabilized by the N-terminal stalk
region and can interact with F. Sialic acid receptors are
displayed at the cell surface, where binding of the individual
HN NA domains could perturb the NA tetramer arrangement,
consistent with the weak interactions between NA domains.
Changes in the HN NA domain tetramer could affect F interactions
and stimulate membrane fusion.
|
|
|
|
|
|
The above figure is
reprinted
by permission from Cell Press:
Structure
(2005,
13,
803-815)
copyright 2005.
|
|
|
|
|
|
|
