Ophiovirus (taxid:88129)

VIRION

Highly flexuous, naked nucleocapsids about 3 to 4 nm in diameter, forming open circles.

GENOME

Segmented negative-stranded RNA linear genome
Contains 3 to 4 segments coding for up to seven proteins.

GENE EXPRESSION

The viral RNA dependent RNA polymerase (L) binds to a promoter on each encapsidated segment, and transcribe a messenger RNA. Translational frameshift may occur on RNA-4 mRNA.

ENZYMES

• RNA-dependent RNA polymerase [L]
• Mononega-type capping
  • RNA TPase, GTase, N7 Mtase, 2'O Mtase [L]

REPLICATION

CYTOPLASMIC

1. Virus enters host cell either carried out by a fungus, or by insect vector: ribonucleocapsid segments are released in the cytoplasm.
2. Transcription, viral mRNAs are capped in the cytoplasm.
3. Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes.
4. The ribonucleocapsids newly synthetized can infect neighbour plant cells or be transported by fungus or insect to new plant.