Enveloped, spherical with a diameter of about 120-150nm.
Segmented Negative-stranded RNA linear genome, L segment is about 6 kb and S segment 3.3 kb.
Encodes for three proteins.
S segment is ambisens. The viral RNA dependent RNA polymerase (L) binds to a promoter on each encapsidated segment, and transcribes a messenger RNA. Transcription is terminated by a strong hairpin sequence at the end of each gene.
- Virus attaches to host receptors though GP glycoprotein and is endocytosed into vesicles in the host cell.
- Fusion of virus membrane with the vesicle membrane; ribonucleocapsid is released in the cytoplasm.
- Sequential transcription, viral mRNAs are capped in the cytoplasm.
- Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes.
- The ribonucleocapsid buds, releasing the virion.