Protein Domain : Cypovirus polyhedrin IPR035239

Type	Family
Description	This family is found in polyhedrin proteins of Cypoviruses. These viruses possess a single capsid layer with turrets and are commonly embedded in crystalline occlusion bodies called polyhedra, which are formed in the cell cytoplasm and mainly composed of a single virus-encoded protein, polyhedron. Cypoviruses have been classified into 21 distinct types. Within each type the amino acid sequence of polyhedrins are highly conserved, whilst between types there is little conservation. Structural analysis and comparison of the different polyhedrins reveals five variable regions: the N-terminal loop, connections between secondary structures (H2 and H3, beta-E and beta-F, beta-F and beta-G, beta-G and beta-H), and the C-terminal loop, which is designate V1-V5 respectively. V2 forms a 'cap' at one end of the protein and is subdivided across two sections of the polypeptide, V2n and V2c. Differences in these regions give each polyhedrin its characteristic appearance. The base domain (residues 74-110) is a region that is neither required for proper folding of the protein, nor for crystal assembly, but fine-tunes the crystal, 'locking-down' the structure, often in conjunction with NTPs. This region is also implicated in virion recognition and packaging [ ].
Short Name	CPV_Polyhedrin