Rhabdoviridae

[1] Vertebrates (including mammals and humans), invertebrates, plants, fungi and protozoans serve as natural hosts.

The name is derived from Ancient Greek rhabdos, meaning rod, referring to the shape of the viral particles.

[6] The individual virus particles (virions) of rhabdoviruses are composed of RNA, protein, carbohydrate and lipid.

[10] In addition to the functions about virus assembly, morphogenesis and budding off enveloped from the host plasma membrane, additional functions such as the regulation of RNA synthesis, affecting the balance of replication and transcription products was found, making reverse genetics experiments with rabies virus, a member of the family Rhabdoviridae.

Transcriptase components are always present in the complete virion to permit rhabdoviruses to begin transcription immediately after entry.

[citation needed] The rhabdovirus transcriptase proceeds in a 3' to 5' direction on the genome and the transcription terminates randomly at the end of protein sequences.

[citation needed] Also, mRNAs accumulate according to the order of protein sequences on the genome, solving the logistics problem in the cell.

All components required for early transcription and the nucleocapsid are released to the cytoplasm of the infected cell after the first steps of binding, penetration and uncoating take place.

[15] The rhabdovirus matrix (M) protein is very small (~20–25 kDa) however plays a number of important roles during the replication cycle of the virus.

[17] Phosphoprotein (P) also plays a crucial role during replication, as N-P complexes, rather than N alone, are necessary for appropriate and selective encapsidation of viral RNA.

During transcription process, the polymerase enzyme may leave the template at any point and then bound just at the 3′ end of the genome RNA to start mRNA synthesis again.

This process will results concentration gradient of the amount of mRNA based on its place and its range from the 3′ end.

This process results in the acquisition of the M + G proteins, responsible for the characteristic bullet- shaped morphology of the virus.

The remaining viruses form a number of highly branched clades and infect arthropods and land vertebrates.

A 2015 analysis of 99 species of animal rhabdoviruses found that they fell into 17 taxonomic groupings, eight – Lyssavirus, Vesiculovirus, Perhabdovirus, Sigmavirus, Ephemerovirus, Tibrovirus, Tupavirus and Sprivivirus – which were previously recognized.

[21] The authors proposed seven new taxa on the basis of their findings: "Almendravirus", "Bahiavirus", "Curiovirus", "Hapavirus", "Ledantevirus", "Sawgravirus" and "Sripuvirus".

This supergroup contains the genera with species that replicate in both vertebrate and invertebrate hosts and have biological cycles that involve transmission by haematophagous dipterans (bloodsucking flies).

Rhabdoviruses are transmitted to hosts by arthropods, such as aphids, planthoppers, leafhoppers, black flies, sandflies, and mosquitoes.

In September 2012, researchers writing in the journal PLOS Pathogens described a novel species of rhabdovirus, called Bas-Congo virus (BASV), which was discovered in a blood sample from a patient who survived an illness that resembled hemorrhagic fever.

[24] Exposure to Ekpoma virus 2 appears to be widespread in certain parts of Nigeria where seroprevalence rates are close to 50%.

Transcription and replication of the vesicular stomatitis virus genome
Replication cycle of vesicular stomatitis virus (VSV)
Electron micrograph illustrating the VSV structure and assembly