Circoviridae

VIRION

Non-enveloped, round, T=1 icosahedral symmetry, about 20 nm in diameter. The capsid consists of 12 pentagonal trumpet-shaped pentamers.

GENOME

Monopartite, circular, ssDNA genome of about 1.8 to 3.8 kb.
The genome is replicated through double-stranded intermediates. The replication (Rep) protein initiates rolling circle replication.

GENE EXPRESSION

One or two mRNAs encode for the Rep, capsid, and possibly others proteins. Some mRNA can undergo alternative splicing.

REPLICATION

NUCLEAR

  1. Virus penetrates into the host cell.
  2. Uncoating, the viral ssDNA genome penetrates into the nucleus.
  3. Viral ssDNA is converted into dsDNA with the participation of cellular factors. dsDNA transcription gives rise to viral mRNAs.
  4. Viral mRNAs are translated to produce viral proteins.
  5. Replication may be mediated by a Rep protein, and would occur by rolling circle replication producing ssDNA genomes.
  6. These newly synthesized ssDNA can either
    a) be converted to dsDNA and serve as a template for transcription/replication
    b) be encapsidated by capsid protein and form virions released by cell lysis.

Host-virus interaction

Autophagy modulation

Cap protein of PCV2 induces activation of host autophagy in order to enhance its own replication .

Apoptosis modulation

PCV2 ORF3-encoded protein induces apoptosis by activating caspase-8 and caspase-3 pathways . This protein may be a candidate for PML bodies inhibition which is essential for nuclear virus replication in mammals.

Matching UniProtKB/Swiss-Prot entries

40 entries grouped by protein (browse by keywords)

All proteins are shown (view only 39 complete proteome entries)

12 entries

Capsid protein (CA1) (Coat protein)

Select_allDeselect_all
CAPSD_BFDV
Beak and feather disease virus (BFDV) reference strain

Capsid protein

CAPSD_CACV
Canary circovirus (CaCV) reference strain

Probable capsid protein

CAPSD_CAVC1
Chicken anemia virus (isolate Germany Cuxhaven-1) (CAV) reference strain
CAPSD_PCV1C
Porcine circovirus 1 (isolate China) (PCV1) reference strain

Capsid protein

CAPSD_CAV26
Chicken anemia virus (isolate USA 26p4) (CAV)
CAPSD_CAV82
Chicken anemia virus (isolate Japan 82-2) (CAV)
CAPSD_CAVAU
Chicken anemia virus (isolate Australia) (CAV)
CAPSD_CAVCA
Chicken anemia virus (isolate Australia/CAU269-7/2000) (CAV)
CAPSD_CAVCI
Chicken anemia virus (isolate USA CIA-1) (CAV)
CAPSD_GOCV
Goose circovirus (GoCV)

Probable capsid protein

CAPSD_PCV2
Porcine circovirus 2 (PCV2)

Capsid protein

CAPSD_PICV
Pigeon circovirus (PiCV) (Columbid circovirus)

Probable capsid protein

1 entry

Protein NS0

NS0_PCV2
Porcine circovirus 2 (PCV2)

2 entries

Protein ORF3

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ORF3_BFDV
Beak and feather disease virus (BFDV) reference strain

Uncharacterized protein ORF3

ORF3_PCV2
Porcine circovirus 2 (PCV2)

1 entry

Uncharacterized protein ORF4

ORF4_BFDV
Beak and feather disease virus (BFDV) reference strain

1 entry

Uncharacterized protein ORF5

ORF5_BFDV
Beak and feather disease virus (BFDV) reference strain

1 entry

Uncharacterized protein ORF6

ORF6_BFDV
Beak and feather disease virus (BFDV) reference strain

1 entry

Uncharacterized protein ORF7

ORF7_BFDV
Beak and feather disease virus (BFDV) reference strain

2 entries

Uncharacterized protein ORFC2

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ORFC2_GOCV
Goose circovirus (GoCV)
ORFC2_PICV
Pigeon circovirus (PiCV) (Columbid circovirus)

1 entry

Uncharacterized protein ORFC3

ORFC3_PICV
Pigeon circovirus (PiCV) (Columbid circovirus)

1 entry

Uncharacterized protein ORFC4

ORFC4_PICV
Pigeon circovirus (PiCV) (Columbid circovirus)

1 entry

Uncharacterized protein ORFV2

ORFV2_GOCV
Goose circovirus (GoCV)

6 entries

Replication-associated protein (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.3) (ATP-dependent helicase Rep) (RepP)

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REP_BFDV
Beak and feather disease virus (BFDV) reference strain
REP_CACV
Canary circovirus (CaCV) reference strain
REP_PCV1C
Porcine circovirus 1 (isolate China) (PCV1) reference strain
REP_GOCV
Goose circovirus (GoCV)
REP_PCV2
Porcine circovirus 2 (PCV2)
REP_PICV
Pigeon circovirus (PiCV) (Columbid circovirus)

5 entries

Dual specificity protein phosphatase VP2 (EC 3.1.3.16) (EC 3.1.3.48)

Select_allDeselect_all
VP2_CAVC1
Chicken anemia virus (isolate Germany Cuxhaven-1) (CAV) reference strain
VP2_CAV26
Chicken anemia virus (isolate USA 26p4) (CAV)
VP2_CAV82
Chicken anemia virus (isolate Japan 82-2) (CAV)
VP2_CAVCA
Chicken anemia virus (isolate Australia/CAU269-7/2000) (CAV)
VP2_CAVCI
Chicken anemia virus (isolate USA CIA-1) (CAV)

5 entries

Apoptin

Select_allDeselect_all
VP3_CAVC1
Chicken anemia virus (isolate Germany Cuxhaven-1) (CAV) reference strain
VP3_CAV26
Chicken anemia virus (isolate USA 26p4) (CAV)
VP3_CAV82
Chicken anemia virus (isolate Japan 82-2) (CAV)
VP3_CAVCA
Chicken anemia virus (isolate Australia/CAU269-7/2000) (CAV)
VP3_CAVCI
Chicken anemia virus (isolate USA CIA-1) (CAV)