Betaflexiviridae

VIRION

Non-enveloped, flexuous, filamentous, 600-1000 nm or more long and 12-13 nm in diameter.

GENOME

Linear ssRNA(+) genome of 6.5-9 kb in size. The 3’ terminus is polyadenylated and, in some genera, the 5’ end is capped. Encodes 2 to 6 proteins.

GENE EXPRESSION

The virion RNA is infectious and serves as both the genome and viral messenger RNA. RNA-dependent RNA polymerase (RdRp) is translated directly from the genomic RNA. The other ORFs are transcribed presumably as monocistronic subgenomic mRNAs (sgRNAs).

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 as a monocistronic mRNA to produce the RdRp (encoded by the 5’-proximal ORF).
  4. Replication occurs in 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. Internal subgenomic promoters are used to transcribe the sgRNAs. Traduction of these sgRNAs yields the capsid and movement proteins.
  7. Assembly of new virus particles.
  8. Triple gene block proteins (TGBp) allow cell-to-cell and long-distance movement.

Host-virus interaction

Suppression of RNA silencing

Potato virus M cysteine-rich protein (ORF6) and TGBp1 proteins act as suppressors of RNA silencing, the former inhibiting both local and systemic silencing, whereas the latter inhibits systemic silencing . Grapevine virus A ORF5 p10 suppresses local and systemic RNA silencing . Citrus leaf blotch virus movement protein acts as suppressor of RNA silencing . Apple chlorotic leaf spot virus 50 kDa movement protein acts as a systemic suppressor of RNA silencing through phloem .

Matching UniProtKB/Swiss-Prot entries

55 entries grouped by strain (browse by keywords)

All proteins are shown (view only 28 complete proteome entries)

6 entries

Potato virus M (strain Russian) (PVM) reference strain

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COAT_PVMRCoat protein (Capsid protein) (CP)
RDRP_PVMRRNA replication polyprotein (ORF1 protein)
TGB1_PVMRMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB2_PVMRMovement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_PVMRMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_PVMRRNA silencing suppressor (10.7 kDa protein) (Putative nucleic acid-binding ...

5 entries

Apple stem pitting virus (isolate PA66) (ASPV) reference strain

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CAPSD_ASPVPCapsid protein (CP) (Coat protein)
RDRP_ASPVPRNA replication polyprotein (ORF1 protein)
TGB1_ASPVPMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB2_ASPVPMovement protein TGB2 (Triple gene block 2 protein) (TGBp2)
TGB3_ASPVPMovement protein TGBp3 (Triple gene block 3 protein) (TGBp3)

5 entries

Grapevine virus A (isolate Is 151) (GVA) reference strain

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CAPSD_GVAISCapsid protein (CP) (Coat protein)
MOVP_GVAISMovement protein (MP)
ORF2_GVAISUncharacterized ORF2 protein
RDRP_GVAISRNA replication protein
VSR_GVAISRNA silencing suppressor

3 entries

Apple chlorotic leaf spot virus (isolate plum P863) (ACLSV) reference strain

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COAT_ACLSPCoat protein
MP_ACLSPPutative movement protein (50.8 kDa protein) (ORF2 protein)
RDRP_ACLSPRNA-directed RNA polymerase (EC 2.7.7.48) (216.5 kDa protein) (ORF1 protein) ...

3 entries

Citrus leaf blotch virus (isolate Nagami kumquat/France/SRA-153/1984) (CLBV) reference strain

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CAPSD_CLBVSCapsid protein (CP) (Coat protein)
MOVP_CLBVSPutative movement protein (MP) (Cell-to-cell transport protein)
RDRP_CLBVSRNA replication polyprotein (ORF1 protein)

2 entries

Apple stem grooving virus (strain P-209) (ASGV) reference strain

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MP_ASGVPProbable movement protein (EC 3.4.21.-) (36 kDa protein) (ORF2 protein)
POLG_ASGVPGenome polyprotein (241 kDa polyprotein) (ORF1 polyprotein)

1 entry

Blueberry scorch virus (BBScV) reference strain


RDRP_BBSCVRNA replication polyprotein (223 kDa protein) (ORF1 protein)

5 entries

Chrysanthemum virus B (CVB)

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COAT_CVBCoat protein (Capsid protein) (CP)
TGB1_CVBMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB2_CVBMovement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_CVBMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_CVBRNA silencing suppressor (12.6 kDa protein) (Putative nucleic acid-binding ...

5 entries

Lily symptomless virus (LSV)

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COAT_LSVCoat protein (Capsid protein) (CP)
TGB1_LSVMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB2_LSVMovement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_LSVMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_LSVRNA silencing suppressor (16 kDa protein) (ORF6 protein) (Putative nucleic ...

5 entries

Potato virus S (strain Peruvian)

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COAT_PVSPCoat protein (Capsid protein) (CP)
TGB1_PVSPMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB2_PVSPMovement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_PVSPMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_PVSPRNA silencing suppressor (10.7 kDa protein) (Putative nucleic acid-binding ...

4 entries

Poplar mosaic virus (isolate ATCC Pv275) (PMV)

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COAT_POPMVCoat protein (Capsid protein) (CP)
TGB1_POPMVMovement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor ...
TGB3_POPMVMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_POPMVRNA silencing suppressor (14 kDa protein) (Putative nucleic acid-binding ...

3 entries

Apple chlorotic leaf spot virus (isolate apple) (ACLSV)

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COAT_ACLSACoat protein
MP_ACLSAPutative movement protein (50.4 kDa protein) (ORF2 protein)
RDRP_ACLSARNA-directed RNA polymerase (EC 2.7.7.48) (216.5 kDa protein) (ORF1 protein) ...

2 entries

Apple stem grooving virus (strain Korea) (ASGV)

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MP_ASGVKPutative movement protein (EC 3.4.21.-) (36 kDa protein) (ORF2 protein)
POLG_ASGVKGenome polyprotein (241 kDa polyprotein) (ORF1 polyprotein)

2 entries

Carnation latent virus (CLV)

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TGB3_CLVMovement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_CLVRNA silencing suppressor (11.6 kDa protein) (Putative nucleic acid-binding ...

2 entries

Helenium virus S (HelVS)

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COAT_HELVSCoat protein (Capsid protein) (CP)
VSR_HELVSRNA silencing suppressor (12.6 kDa protein) (Putative nucleic acid-binding ...

2 entries

Potato virus M (strain German) (PVM)

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COAT_PVMGCoat protein (Capsid protein) (CP)
VSR_PVMGRNA silencing suppressor (12 kDa protein) (Cysteine-rich protein) (CRP) ...