2ygb
From Proteopedia
Structure of vaccinia virus D13 scaffolding protein
Structural highlights
FunctionD13_VACCW Scaffold protein which forms a transitory spherical honeycomb lattice providing curvature and rigidity to the convex membrane of crescent and immature virions (IV). This association occurs concomitantly with viral membrane formation. Targeted by the drug rifampicin, which prevents the formation of this lattice, and hence virus morphogenesis. In the presence of rifampicin, irregularly shaped membranes that lack the honeycomb layer accumulate around areas of electron-dense viroplasm. This layer is lost from virions during maturation from IV to mature virion (MV), through the proteolysis of A17 N-terminus. Publication Abstract from PubMedThe morphogenesis of poxviruses such as vaccinia virus (VACV) sees the virion shape mature from spherical to brick-shaped. Trimeric capsomers of the VACV D13 protein form a transitory, stabilizing lattice on the surface of the initial spherical immature virus particle. The crystal structure of D13 reveals that this major scaffolding protein comprises a double beta barrel "jelly-roll" subunit arranged as pseudo-hexagonal trimers. These structural features are characteristic of the major capsid proteins of a lineage of large icosahedral double-stranded DNA viruses including human adenovirus and the bacteriophages PRD1 and PM2. Structure-based phylogenetic analysis confirms that VACV belongs to this lineage, suggesting that (analogously to higher organism embryogenesis) early poxvirus morphogenesis reflects their evolution from a lineage of viruses sharing a common icosahedral ancestor. Insights into the evolution of a complex virus from the crystal structure of vaccinia virus d13.,Bahar MW, Graham SC, Stuart DI, Grimes JM Structure. 2011 Jul 13;19(7):1011-20. PMID:21742267[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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