Coltivirus

VIRION

Non enveloped, icosahedral virion with a triple capsid structure, about 60-80 nm in diameter. Pentameric turrets sit on the outside of the innermost capsid. The intermediate capsid has a T=13 icosahedral symmetry, the inner capsid a T=2* icosahedral symmetry.

GENOME

Segmented dsRNA linear genome. Contains 12 segments coding for 13 proteins. Segments size range from 675 to 4,350 bp and genome total size is about 29,000 bp (CTFV).

GENE EXPRESSION

The dsRNA genome is never completely uncoated, to prevent activation of antiviral state by the cell in response to dsRNA. The viral polymerase VP1 synthesizes a capped mRNA from each dsRNA segment. This capped mRNA is translocated to the cell cytoplasm where it is translated. VP9 protein is expressed via RNA suppression of termination.

REPLICATION

CYTOPLASMIC

  1. Attachement to host receptors probably mediates endocytosis of virus into host cell.
  2. Particles are partially uncoated in endolysosomes, but not entirely, and penetrate in the cytoplasm.
  3. Early transcription of the dsRNA genome by viral polymerase occurs inside this sub-viral particle (naked core), so that dsRNA is never exposed to the cytoplasm.
  4. Full-length plus-strand transcripts from each of the dsRNA segments are synthesized. These plus-strand transcripts are used as templates for translation.
  5. Viral proteins and genomic RNAs aggregates in cytoplasmic viral factories.
  6. (+)RNAs are encapsidated in a sub-viral particle, in which they are transcribed to give RNA (-) molecules with which they become base-paired to produce dsRNA genomes.
  7. The capsid is assembled on the sub-viral particle.
  8. Mature virions are released presumably following cell death and associated breakdown of host plasma membrane.

Matching UniProtKB/Swiss-Prot entries

13 entries grouped by protein (browse by keywords)

1 entry

RNA-directed RNA polymerase VP1 (EC 2.7.7.48)

RDRP_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Microtubule-associated protein VP10

VP10_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP11

VP11_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP12

VP12_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Putative RNA methyltransferase VP2 (EC 2.1.1.-)

VP2_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP3

VP3_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP4

VP4_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP5

VP5_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP6

VP6_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP7

VP7_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Uncharacterized protein VP8

VP8_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Structural protein VP9

VP9_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain

1 entry

Non structural protein VP9'

VP9P_CTFVL
Colorado tick fever virus (strain USA/Florio N-7180) (CTFV) reference strain