VIRION
Non-enveloped icosahedral capsid, about 35-40 nm in diameter with a T=2* icosahedral symmetry . The two genomic segments are encapsidated separately.
Backbone trace of partitivirus capsid protein from electron cryomicroscopy and homology modeling
Jinghua Tang, Junhua Pan, Wendy M. Havens, Wendy F. Ochoa, Tom S. Y. Guu, Said A. Ghabrial, Max L. Nibert, Yizhi Jane Tao, Timothy S. Baker
Biophys. J. July 21, 2010; 99: 685?694
Jinghua Tang, Junhua Pan, Wendy M. Havens, Wendy F. Ochoa, Tom S. Y. Guu, Said A. Ghabrial, Max L. Nibert, Yizhi Jane Tao, Timothy S. Baker
Biophys. J. July 21, 2010; 99: 685?694
GENOME
Segmented dsRNA linear genome: 2 segments encoding potentially for 2 proteins. Segments are about 2.1 kb each, total size about 4 kb.
GENE EXPRESSION
Each genomic segment is monocistronic.
ENZYMES
REPLICATION
CYTOPLASMIC
- Virus penetrates into the cytoplasm.
- Transcription of the dsRNA genome by viral polymerase occurs inside the virion, so that dsRNA is never exposed to the cytoplasm. This plus-strand transcript is used as template for translation.
- (+)RNAs are encapsidated in virion particle, inside which they are transcribed to give RNA (-) molecules with which they become base-paired to produce dsRNA genomes.
- Mature are transmitted to new cell during cell division, sporogenesis or cell fusion.