Togaviridae

VIRION

Enveloped, spherical, icosahedral, 65-70nm in diameter, capsid with a T=4 icosahedral symmetry made of 240 monomers. The envelope contains 80 trimer spikes, each spike = 3 x E1/E2 heterodimers.

GENOME

Monopartite, linear, ssRNA(+) genome of 9.7-11.8 kb. The genome is capped and polyadenylated.

GENE EXPRESSION

The virion RNA is infectious and serves as both genome and viral messenger RNA. The whole genome is translated into a non-structural polyprotein which is processed by host and viral proteases. Structural polyprotein is expressed through a subgenomic mRNA.
In alphaviruses, RdRp is expressed by suppression of termination at the end of 10% of nsP polyproteins. Moreover a ribosomal frameshifting in the 6K region induces the translation of the TF protein in alphaviruses.

REPLICATION

CYTOPLASMIC

  1. Attachement of the viral E glycoprotein to host receptors mediates clathrin-mediated endocytosis of virus into the host cell.
  2. Fusion of virus membrane with host endosomal membrane. RNA genome is released into the cytoplasm.
  3. The positive-sense genomic ssRNA is translated into a polyprotein, which is cleaved into non-structural proteins necessary for RNA synthesis (replication and transcription).
  4. Replication takes place in cytoplasmic viral factories at the surface of endosomes. A dsRNA genome is synthesized from the genomic ssRNA(+).
  5. The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA(+) genomes.
  6. Expression of the subgenomic RNA (sgRNA) gives rise to the structural proteins.
  7. Capsid assembly occurs in cytoplasm.
  8. The capsid is envelopped by budding at the plasma membrane where the virion exits the cell.

Host-virus interaction

Autophagy modulation

Chikungunya probably activates an autophagic process which promotes viral replication .

Host gene expression shutoff by virus

Togaviruses mediate host translation shutoff.
Alphaviruses induce strong PKR activation leading to leading to the almost complete phosphorylation of eIF2alpha and host translation arrest .
Rubella virus capsid protein (Rubivirus) seems to mediate host translation shutoff by inhibiting host poly(A)-binding protein .

Alphaviruses perform host transcription shutoff by inhibiting host RNA polymerase II. Host RNA-pol II catalytic subunit is targeted for degradation as early as 4-6h p.i. .

Matching UniProtKB/Swiss-Prot entries

50 entries grouped by strain (browse by keywords)

Only complete proteome entries are shown (view all 59 entries)

3 entries

Chikungunya virus (strain S27-African prototype) (CHIKV) reference strain

Select_allDeselect_all
POLN_CHIKS Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123 (P123); ...
POLSF_CHIKS Frameshifted structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat ...
POLS_CHIKS Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Semliki forest virus (SFV) reference strain

Select_allDeselect_all
POLN_SFV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_SFV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

3 entries

Sindbis virus (SINV) reference strain

Select_allDeselect_all
POLN_SINDV Polyprotein P1234 (P1234) (Non-structural polyprotein) (p270 nonstructural polyprotein) [Cleaved ...
POLS_SINDV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLSF_SINDV Frameshifted structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat ...

1 entry

Semliki forest virus (SFV)

POLSF_SFV Frameshifted structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat ...

2 entries

Aura virus (AURAV)

Select_allDeselect_all
POLN_AURAV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_AURAV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Barmah forest virus (BFV)

Select_allDeselect_all
POLN_BFV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_BFV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Chikungunya virus (strain 37997) (CHIKV)

Select_allDeselect_all
POLN_CHIK3 Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_CHIK3 Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Eastern equine encephalitis virus (strain Florida 91-469) (EEEV) (Eastern equine encephalomyelitis virus)

Select_allDeselect_all
POLN_EEEVF Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_EEEVF Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Eastern equine encephalitis virus (strain PE-0.0155) (EEEV) (Eastern equine encephalomyelitis virus)

Select_allDeselect_all
POLN_EEEV1 Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_EEEV1 Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Eastern equine encephalitis virus (strain PE-3.0815) (EEEV) (Eastern equine encephalomyelitis virus)

Select_allDeselect_all
POLS_EEEV8 Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_EEEV8 Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Getah virus (GETV)

Select_allDeselect_all
POLS_GETV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_GETV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Mayaro virus (strain Brazil) (MAYV)

Select_allDeselect_all
POLS_MAYAB Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_MAYAB Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

O'nyong-nyong virus (strain Gulu) (ONNV)

Select_allDeselect_all
POLS_ONNVG Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_ONNVG Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123 (P123); ...

2 entries

O'nyong-nyong virus (strain Igbo Ora) (ONNV) (Igbo Ora virus)

Select_allDeselect_all
POLN_ONNVI Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123 (P123); ...
POLS_ONNVI Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

O'nyong-nyong virus (strain SG650) (ONNV)

Select_allDeselect_all
POLS_ONNVS Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_ONNVS Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Ross river virus (strain NB5092) (RRV)

Select_allDeselect_all
POLS_RRVN Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_RRVN Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Sagiyama virus (SAGV)

Select_allDeselect_all
POLS_SAGV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_SAGV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Salmon pancreas disease virus (SPDV)

Select_allDeselect_all
POLS_SPDV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_SPDV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123 (P123); ...

2 entries

Sindbis virus subtype Ockelbo (strain Edsbyn 82-5) (OCKV) (Ockelbo virus)

Select_allDeselect_all
POLS_SINDO Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_SINDO Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Sleeping disease virus (SDV)

Select_allDeselect_all
POLN_SLDV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123 (P123); ...
POLS_SLDV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Venezuelan equine encephalitis virus (strain 3880) (VEEV)

Select_allDeselect_all
POLN_EEVV3 Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...
POLS_EEVV3 Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...

2 entries

Venezuelan equine encephalitis virus (strain P676) (VEEV)

Select_allDeselect_all
POLS_EEVVP Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_EEVVP Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Venezuelan equine encephalitis virus (strain Trinidad donkey) (VEEV)

Select_allDeselect_all
POLS_EEVVT Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_EEVVT Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

2 entries

Western equine encephalitis virus (WEEV)

Select_allDeselect_all
POLS_WEEV Structural polyprotein (p130) [Cleaved into: Capsid protein (EC 3.4.21.90) (Coat protein) (C); ...
POLN_WEEV Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...

1 entry

Venezuelan equine encephalitis virus (strain Mena II) (VEEV)

POLN_EEVVM Polyprotein P1234 (P1234) (Non-structural polyprotein) [Cleaved into: Polyprotein P123' (P123'); ...