Tombusvirus (taxid:12141)

VIRION

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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).
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GENOME

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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 protein

5 entries

Capsid protein (Coat protein) (p41)

Select_allDeselect_all
CAPSD_AMCV
Artichoke mottled crinkle virus (AMCV) reference strain
CAPSD_TBSVC
Tomato bushy stunt virus (strain Cherry) (TBSV) reference strain
CAPSD_CNV
Cucumber necrosis virus (CNV)
CAPSD_CRV
Cymbidium ringspot virus (CymRSV)
CAPSD_TBSVB
Tomato bushy stunt virus (strain BS-3) (TBSV)

2 entries

Movement protein p22 (p21)

Select_allDeselect_all
MP22_TBSVK
Tomato bushy stunt virus (strain Ja9) (TBSV)
MP22_TBSVT
Tomato bushy stunt virus (strain type) (TBSV)

8 entries

Movement protein (p22)

Select_allDeselect_all
MVP_TBSVC
Tomato bushy stunt virus (strain Cherry) (TBSV) reference strain
MVP_AMCV
Artichoke mottled crinkle virus (AMCV)
MVP_CNV
Cucumber necrosis virus (CNV)
MVP_CRV
Cymbidium ringspot virus (CymRSV)
MVP_TBSV8
Tomato bushy stunt virus (strain B8) (TBSV)
MVP_TBSVA
Tomato bushy stunt virus (strain A23) (TBSV)
MVP_TBSVB
Tomato bushy stunt virus (strain BS-3) (TBSV)
MVP_TBSVJ
Tomato bushy stunt virus (strain Ja6) (TBSV)

14 entries

RNA silencing suppressor p19 (19 kDa symptom severity modulator)

Select_allDeselect_all
P19_TBSVC
Tomato bushy stunt virus (strain Cherry) (TBSV) reference strain
P19_AMCV
Artichoke mottled crinkle virus (AMCV)
P19_CIRV
Carnation Italian ringspot virus (CIRV)
P19_CNV
Cucumber necrosis virus (CNV)
P19_CRV
Cymbidium ringspot virus (CymRSV)
P19_HARV
Havel river virus (HaRV)
P19_PENSV
Pelargonium necrotic spot virus (PeNSV)
P19_PLV
Pear latent virus (PeLV)
P19_TBSV8
Tomato bushy stunt virus (strain B8) (TBSV)
P19_TBSVA
Tomato bushy stunt virus (strain A23) (TBSV)
P19_TBSVB
Tomato bushy stunt virus (strain BS-3) (TBSV)
P19_TBSVJ
Tomato bushy stunt virus (strain Ja6) (TBSV)
P19_TBSVK
Tomato bushy stunt virus (strain Ja9) (TBSV)
P19_TBSVT
Tomato bushy stunt virus (strain type) (TBSV)

3 entries

RNA-directed RNA polymerase (EC 2.7.7.48) (Protein p92)

Select_allDeselect_all
RDRP_TBSVC
Tomato bushy stunt virus (strain Cherry) (TBSV) reference strain
RDRP_CNV
Cucumber necrosis virus (CNV)
RDRP_CRV
Cymbidium ringspot virus (CymRSV)