Tombusvirus (taxid:12141)

VIRION

image

Non-enveloped, spherical, icosahedral, about 28-34 nm in diameter, capsid with a T=3 icosahedral symmetry. 30 hexameric capsomers per nucleocapsid (virion composed of 180 protein subunits).
image

GENOME

image

Monopartite, linear, ssRNA(+) genome of 4-5.4 kb, which lacks a cap structure and a poly(A)tail.

GENE EXPRESSION

The virion RNA is infectious and serves as both the genome and viral messenger RNA. Two 5'-proximal ORFs are directly translated to produce the viral constituents of the replicase complex. RdRp is translated through suppression of termination at the end of ORF1. The downstream genes encoding the movement protein, viral suppressor of RNA silencing (VSR) and capsid proteins are translated from subgenomic RNAs.
Cap-independent translation is mediated possibly through the interaction between a 3'-cap-independent translation element and a 5'UTR stem-loop.

ENZYMES

REPLICATION

CYTOPLASMIC

  1. Virus penetrates into the host cell.
  2. Uncoating, and release of the viral genomic RNA into the cytoplasm.
  3. The viral RNA is translated to produce the two proteins necessary for RNA synthesis (replication and transcription).
  4. Replication takes place in cytoplasmic viral factories. A dsRNA genome is synthesized from the genomic ssRNA(+).
  5. The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA(+) genomes.
  6. The RdRp recognizes internal subgenomic promoters on the negative-sense RNA to transcribe the 3'co-terminal subgenomic RNAs that will generate the capsid and movement protein.
  7. The RdRp recognizes internal subgenomic promoters on the negative-sense RNA to transcribe the 3'co-terminal subgenomic RNAs that will generate the capsid protein, movement protein and viral suppressor of RNA silencing (VSR).
  8. Virus assembly in the cytoplasm.
  9. Viral movement protein probably mediates virion cell-to-cell transfer.

Host-virus interaction

Suppression of RNA silencing

Tombusviruses encode P19/P20 protein acting as a suppressor of RNA silencing .

Matching UniProtKB/Swiss-Prot entries

(all links/actions below point to uniprot.org website)

32 entries grouped by strain

4 entries

Tomato bushy stunt virus (strain Cherry) (TBSV) reference strain

Select_allDeselect_all
P19_TBSVC RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_TBSVC Movement protein (p22)
CAPSD_TBSVC Capsid protein (Coat protein) (p41)
RDRP_TBSVC RNA-directed RNA polymerase (EC 2.7.7.48) (Protein p92) [Cleaved into: Protein p33]

4 entries

Cucumber necrosis virus (CNV)

Select_allDeselect_all
CAPSD_CNV Capsid protein (Coat protein) (p41)
P19_CNV RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_CNV Movement protein (p22)
RDRP_CNV RNA-directed RNA polymerase (EC 2.7.7.48) (Protein p92) [Cleaved into: Protein p33]

4 entries

Cymbidium ringspot virus (CymRSV)

Select_allDeselect_all
CAPSD_CRV Capsid protein (Coat protein) (p41)
P19_CRV RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_CRV Movement protein (p22)
RDRP_CRV RNA-directed RNA polymerase (EC 2.7.7.48) (Protein p92) [Cleaved into: Protein p33]

3 entries

Artichoke mottled crinkle virus (AMCV)

Select_allDeselect_all
CAPSD_AMCV Capsid protein (Coat protein) (p41)
P19_AMCV RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_AMCV Movement protein (p22)

3 entries

Tomato bushy stunt virus (strain BS-3) (TBSV)

Select_allDeselect_all
CAPSD_TBSVB Capsid protein (Coat protein) (p41)
P19_TBSVB RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_TBSVB Movement protein (p22)

2 entries

Tomato bushy stunt virus (strain A23) (TBSV)

Select_allDeselect_all
P19_TBSVA RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_TBSVA Movement protein (p22)

2 entries

Tomato bushy stunt virus (strain B8) (TBSV)

Select_allDeselect_all
P19_TBSV8 RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MVP_TBSV8 Movement protein (p22)

2 entries

Tomato bushy stunt virus (strain Ja6) (TBSV)

Select_allDeselect_all
MVP_TBSVJ Movement protein (p22)
P19_TBSVJ RNA silencing suppressor p19 (19 kDa symptom severity modulator)

2 entries

Tomato bushy stunt virus (strain Ja9) (TBSV)

Select_allDeselect_all
MP22_TBSVK Movement protein p22 (p21)
P19_TBSVK RNA silencing suppressor p19 (19 kDa symptom severity modulator)

2 entries

Tomato bushy stunt virus (strain type) (TBSV)

Select_allDeselect_all
P19_TBSVT RNA silencing suppressor p19 (19 kDa symptom severity modulator)
MP22_TBSVT Movement protein p22 (p21)

1 entry

Carnation Italian ringspot virus (CIRV)

P19_CIRV RNA silencing suppressor p19 (19 kDa symptom severity modulator)

1 entry

Havel river virus (HaRV)

P19_HARV RNA silencing suppressor p19 (19 kDa symptom severity modulator)

1 entry

Pear latent virus (PeLV)

P19_PLV RNA silencing suppressor p19 (19 kDa symptom severity modulator)

1 entry

Pelargonium necrotic spot virus (PeNSV)

P19_PENSV RNA silencing suppressor p19 (19 kDa symptom severity modulator)