Structural analysis of the human metapneumovirus matrix protein reveals a high-affinity calcium binding site and a positively charged patch involved in membrane interaction and self-assembly.
The structural characterization of the human metapneumovirus matrix protein reveals calcium binding sites that may play a role in viral replication and morphogenesis.
The matrix protein (M) of paramyxoviruses plays a key role in determining virion morphology by directing viral assembly and budding. Here, we report the crystal structure of the human metapneumovirus M at 2.8 Å resolution in its native dimeric state. The structure reveals the presence of a high-affinity Ca²⁺ binding site. Molecular dynamics simulations (MDS) predict a secondary lower-affinity site that correlates well with data from fluorescence-based thermal shift assays. By combining small-angle X-ray scattering with MDS and ensemble analysis, we captured the structure and dynamics of M in solution. Our analysis reveals a large positively charged patch on the protein surface that is involved in membrane interaction. Structural analysis of DOPC-induced polymerization of M into helical filaments using electron microscopy leads to a model of M self-assembly. The conservation of the Ca²⁺ binding sites suggests a role for calcium in the replication and morphogenesis of pneumoviruses.
Leyrat et al. (Thu,) conducted a other in Human Metapneumovirus. Structural analysis of the human metapneumovirus matrix protein reveals a high-affinity calcium binding site and a positively charged patch involved in membrane interaction and self-assembly.