Fimoviridae

VIRION

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Enveloped, spherical.

GENOME

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The genome is segmented and consists of four segments of linear negative-sense and single-stranded RNA. The complete genome is around 12.2 kb.

GENE EXPRESSION

The viral RNA dependent RNA polymerase (L) binds to a promoter on each encapsidated segment, and transcribes the mRNAs. These are capped by L protein during synthesis using cap snatching

REPLICATION

CYTOPLASMIC

  1. Virus attaches to host receptors.
  2. Fusion of virus membrane with the cell membrane; ribonucleocapsid segments are released in the cell.
  3. Transcription, viral mRNAs are capped in the cytoplasm.
  4. Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes.
  5. The ribonucleocapsids buds from a cellular membrane, releasing the virion.