Bicaudaviridae is a family of hyperthermophilic archaeal viruses. Members of the genus Acidianus serve as natural hosts. There is only one genus, Bicaudavirus, and one species, Acidianus two-tailed virus (Bicaudavirus pozzuoliense), in this family.[1][2][3][4] However, Sulfolobus tengchongensis spindle-shaped viruses 1 and 2 (STSV1 and STSV2) are regarded to belong to this family also.[5]
Genome organization of Acidianus two-tailed virus showing location, sizes and transcriptional direction of the putative genes
Viruses in Bicaudaviridae are non-enveloped, with lemon-shaped geometries. Genomes are circular dsDNA molecules of around 48–76 kb in length. High-resolution structure was determined by cryo-EM for Sulfolobus monocaudavirus 1 (SMV1) and a lower-resolution structure was determined for Acidianus two-tailed virus (ATV).[6] Virions of both viruses have helical symmetry, with continuous 7-start helices, composed of the single major capsid protein, forming both the tails and the spindle-shaped body. The major capsid protein structure and virion organization of bicaudaviruses are similar to those of archaeal viruses from the families Fuselloviridae, Thaspiviridae, Halspiviridae and Clavaviridae.[6]
Genus
Structure
Symmetry
Capsid
Genomic arrangement
Genomic segmentation
Bicaudavirus
Lemon-shaped
Helical (C7)
Non-enveloped
Circular
Monopartite
Life cycle
Electron micrographs of different forms of Acidianus two-tailed virus
Viral replication is cytoplasmic. Entry into the host cell is achieved by attachment of the viral proteins to host receptors. DNA-templated transcription is the method of transcription. Diverse species of hyperthermophilic archaea from the order Sulfolobales serve as the natural hosts. Transmission routes are passive diffusion.[2] It has been demonstrated that certain members of the family, namely, STSV2 and Sulfolobus monocaudavirus 1 (SMV1), induce cell gigantism by blocking the expression of the cell division genes and arresting the cell cycle in the S phase.[7] The diameter of infected cells increases up to 20 times, resulting in 8,000-fold increase in volume compared to noninfected cells.[7]
Genus
Host details
Tissue tropism
Entry details
Release details
Replication site
Assembly site
Transmission
Bicaudavirus
Archea: acidianus
None
Injection
Budding
Cytoplasm
Cytoplasm
Passive diffusion
History
This family was first described by the team led by D. Prangishvili in 2005.[8][9]
The name is derived from the Latin word 'bi' and 'cauda' meaning 'two-tail'.
↑ Häring M, Vestergaard G, Rachel R, Chen L, Garrett RA and Prangishvili D (2005) Independent virus development outside a host. Nature 436, 1101–1102
↑ Prangishvili, D., Vestergaard G, Häring M, Aramayo R, Basta T, Rachel R and Garrett RA (2006) Structural and genomic properties of the hyperthermophilic archaeal virus ATV with an extracellular stage of the reproductive cycle. J. Mol. Biol. 359, 1203–1216
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
