TABLE 1.
Comparison of the main characteristics of viruses of the family Partitiviridae and a CPV
| Property | Partitiviridaea | CPVb |
|---|---|---|
| Localization in the host cell | Cytoplasm | Cytoplasm |
| Particle diameter (nm) | 30–40 | 31 |
| Shape of virion | Isometric, nonenveloped | Isometric, nonenveloped |
| Density in CsCl (g/ml) | 1.34–1.39 | 1.35–1.46 |
| Stability of virion | Stable in butanol and chloroform | Stable in butanol and chloroform |
| Capsid protein | Single capsid protein, 42–73 or 125 kDa | May be a single capsid protein, 37 kDa |
| Nucleic acids | Two monocistronic dsRNA segments, 1.4–3.0 kbp, each segment separately encapsidated | Two monocistronic dsRNA segments, 1.4 and 1.7 kbp, each segment separately encapsidated |
| Satellite and defective dsRNAs | Some viruses contain additional dsRNA segments, which are considered satellite or defective | Not found |
| Large dsRNA segment | Encodes RDRP | Encodes RDRP |
| Small dsRNA segment | Encodes capsid protein | May encode capsid protein |
| Mode of transcription | Semiconservative | Semiconservative |
| RNA polymerase activity | Associated with virion | Associated with virion |
| Particles with RI | Particles with ssRNA and particles with both dsRNA and ssRNA | Particles with ssRNA and particles with both dsRNA and ssRNA |
| Mode of transmission | Do not have extracellular phase; transmitted vertically | Unknown |
| Host | Fungi, plants | Protozoan parasite C. parvum, both genotype 1 and genotype 2 |
| Genera | Partitivirus, Chrysovirus, Alphacryptovirus, Betacryptovirus | May represent new genus according to protozoan host |
| Effect on host | Many with no effect | Unknown |