Structural highlights
Function
[GAG_RSVP] Capsid protein p27 forms the spherical core of the virus that encapsulates the genomic RNA-nucleocapsid complex (By similarity). The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell (By similarity).
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The structure of the N-terminal domain (NTD) of Rous sarcoma virus (RSV) capsid protein (CA), with an upstream 25 amino acid residue extension corresponding to the C-terminal portion of the Gag p10 protein, has been determined by X-ray crystallography. Purified Gag proteins of retroviruses can assemble in vitro into virus-like particles closely resembling in vivo-assembled immature virus particles, but without a membrane. When the 25 amino acid residues upstream of CA are deleted, Gag assembles into tubular particles. The same phenotype is observed in vivo. Thus, these residues act as a "shape determinant" promoting spherical assembly, when they are present, or tubular assembly, when they are absent. We show that, unlike the NTD on its own, the extended NTD protein has no beta-hairpin loop at the N terminus of CA and that the molecule forms a dimer in which the amino-terminal extension forms the interface between monomers. Since dimerization of Gag has been inferred to be a critical step in assembly of spherical, immature Gag particles, the dimer interface may represent a structural feature that is essential in retrovirus assembly.
Dimeric rous sarcoma virus capsid protein structure relevant to immature Gag assembly.,Nandhagopal N, Simpson AA, Johnson MC, Francisco AB, Schatz GW, Rossmann MG, Vogt VM J Mol Biol. 2004 Jan 2;335(1):275-82. PMID:14659756[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Nandhagopal N, Simpson AA, Johnson MC, Francisco AB, Schatz GW, Rossmann MG, Vogt VM. Dimeric rous sarcoma virus capsid protein structure relevant to immature Gag assembly. J Mol Biol. 2004 Jan 2;335(1):275-82. PMID:14659756
