Molecular biology

VIRION

No true virion, capsid-less virus.

GENOME

Linear ssRNA(+) genome of about 5.5 kb in size. The 3’ terminus is polyadenylated.

GENE EXPRESSION

The virion RNA is infectious and serves as both the genome and viral messenger RNA. The genome has one ORF encoding the RNA-dependent RNA polymerase (RdRp).

REPLICATION

CYTOPLASMIC

1. Virus penetrates into the host cell.
2. The viral RNA is translated as a monocistronic mRNA to produce the RdRp.
3. A negative-sense complementary ssRNA is synthesized using the genomic RNA as a template.
4. New genomic RNA is synthesized using the negative-sense RNA as a template.