Virions consist of four to five non enveloped nucleocapsids, about 3-10 nm in diameter
The genome is segmented and consists of four or five segments of linear negative-sense and ambisense single-stranded RNA. The complete genome is around 16 kb.
Segments 2, 3 and 4 are ambisens.
CYTOPLASMIC# Virus attaches to host receptors surface proteins, and is endocytosed into vesicles in the host cell. # Fusion of virus membrane with the vesicle membrane; ribonucleocapsid segments are released in the cytoplasm. # Transcription, viral mRNAs are capped in the cytoplasm. # Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes. # The ribonucleocapsids migrate under the plasma membrane and buds, releasing the virion.