Betaflexiviridae (taxid:675068)

VIRION

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

GENOME

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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).

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 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

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

55 entries grouped by strain

6 entries

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

Select_allDeselect_all
RDRP_PVMR RNA replication polyprotein (ORF1 protein) [Cleaved into: Helicase (EC 3.6.4.13)] [Includes: Viral ...
TGB1_PVMR Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB2_PVMR Movement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_PVMR Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
CAPSD_PVMR Capsid protein (Coat protein) (CP)
VSR_PVMR RNA silencing suppressor (10.7 kDa protein) (Putative nucleic acid-binding protein)

5 entries

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

Select_allDeselect_all
RDRP_ASPVP RNA replication polyprotein (ORF1 protein) [Cleaved into: Helicase (EC 3.6.4.13)] [Includes: Viral ...
TGB1_ASPVP Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB2_ASPVP Movement protein TGB2 (Triple gene block 2 protein) (TGBp2)
TGB3_ASPVP Movement protein TGBp3 (Triple gene block 3 protein) (TGBp3)
CAPSD_ASPVP Capsid protein (CP) (Coat protein)

5 entries

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

Select_allDeselect_all
RDRP_GVAIS RNA replication protein [Includes: RNA-directed RNA polymerase (EC 2.7.7.48); Helicase (EC ...
VSR_GVAIS RNA silencing suppressor
ORF2_GVAIS Uncharacterized ORF2 protein
MOVP_GVAIS Movement protein (MP)
CAPSD_GVAIS Capsid protein (CP) (Coat protein)

3 entries

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

Select_allDeselect_all
RDRP_ACLSP RNA-directed RNA polymerase (EC 2.7.7.48) (216.5 kDa protein) (ORF1 protein) (RNA replicase)
MP_ACLSP Putative movement protein (50.8 kDa protein) (ORF2 protein)
CAPSD_ACLSP Capsid protein (Coat protein) (CP)

3 entries

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

Select_allDeselect_all
RDRP_CLBVS RNA replication polyprotein (ORF1 protein) [Includes: Viral methyltransferase (EC 2.1.1.-); Putative ...
CAPSD_CLBVS Capsid protein (CP) (Coat protein)
MOVP_CLBVS Putative movement protein (MP) (Cell-to-cell transport protein)

2 entries

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

Select_allDeselect_all
POLG_ASGVP Genome polyprotein (241 kDa polyprotein) (ORF1 polyprotein) [Cleaved into: Putative RNA-directed RNA ...
MP_ASGVP Probable movement protein (EC 3.4.21.-) (36 kDa protein) (ORF2 protein)

1 entry

Blueberry scorch virus (BBScV) reference strain

RDRP_BBSCV RNA replication polyprotein (223 kDa protein) (ORF1 protein) [Cleaved into: Helicase (EC 3.6.4.13)] ...

5 entries

Chrysanthemum virus B (CVB)

Select_allDeselect_all
TGB1_CVB Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB2_CVB Movement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_CVB Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
CAPSD_CVB Capsid protein (Coat protein) (CP)
VSR_CVB RNA silencing suppressor (12.6 kDa protein) (Putative nucleic acid-binding protein)

5 entries

Lily symptomless virus (LSV)

Select_allDeselect_all
TGB1_LSV Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB2_LSV Movement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_LSV Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
CAPSD_LSV Capsid protein (Coat protein) (CP)
VSR_LSV RNA silencing suppressor (16 kDa protein) (ORF6 protein) (Putative nucleic acid-binding protein)

5 entries

Potato virus S (strain Peruvian)

Select_allDeselect_all
TGB1_PVSP Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB2_PVSP Movement protein TGB2 (12 kDa protein) (Triple gene block 2 protein) (TGBp2)
TGB3_PVSP Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
CAPSD_PVSP Capsid protein (Coat protein) (CP)
VSR_PVSP RNA silencing suppressor (10.7 kDa protein) (Putative nucleic acid-binding protein)

4 entries

Poplar mosaic virus (isolate ATCC Pv275) (PMV)

Select_allDeselect_all
CAPSD_POPMV Capsid protein (Coat protein) (CP)
TGB1_POPMV Movement and silencing protein TGBp1 (25 kDa protein) (Silencing suppressor P25) (Triple gene block ...
TGB3_POPMV Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)
VSR_POPMV RNA silencing suppressor (14 kDa protein) (Putative nucleic acid-binding protein)

3 entries

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

Select_allDeselect_all
RDRP_ACLSA RNA-directed RNA polymerase (EC 2.7.7.48) (216.5 kDa protein) (ORF1 protein) (RNA replicase)
MP_ACLSA Putative movement protein (50.4 kDa protein) (ORF2 protein)
CAPSD_ACLSA Capsid protein (Coat protein) (CP)

2 entries

Apple stem grooving virus (strain Korea) (ASGV)

Select_allDeselect_all
POLG_ASGVK Genome polyprotein (241 kDa polyprotein) (ORF1 polyprotein) [Cleaved into: Putative RNA-directed RNA ...
MP_ASGVK Putative movement protein (EC 3.4.21.-) (36 kDa protein) (ORF2 protein)

2 entries

Carnation latent virus (CLV)

Select_allDeselect_all
VSR_CLV RNA silencing suppressor (11.6 kDa protein) (Putative nucleic acid-binding protein)
TGB3_CLV Movement protein TGBp3 (7 kDa protein) (Triple gene block 3 protein) (TGBp3)

2 entries

Helenium virus S (HelVS)

Select_allDeselect_all
CAPSD_HELVS Capsid protein (Coat protein) (CP)
VSR_HELVS RNA silencing suppressor (12.6 kDa protein) (Putative nucleic acid-binding protein)

2 entries

Potato virus M (strain German) (PVM)

Select_allDeselect_all
CAPSD_PVMG Capsid protein (Coat protein) (CP)
VSR_PVMG RNA silencing suppressor (12 kDa protein) (Cysteine-rich protein) (CRP) (Nucleic acid-binding ...