Nanovirus (taxid:104766)

VIRION

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Non-enveloped, round, T=1 icosahedral symmetry, about 18-19 nm in diameter.
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GENOME

Multipartite ssDNA genome (+) composed of 6 to 8 circular segments about 1kb in size. Each ssDNA segment have a common stem-loop region and are encapsidated in a separate particle.
In addition to genomic DNA, up to 4 satellite-like DNAs are commonly found, usually encoding for accessory Rep proteins (para-Rep). These satellite-rep proteins are only able to initiate replication of their genomic DNA, unlike genomic encoded Master-Rep (M-Rep) which promotes replication of all 6-8 viral genomic ssDNAs (trans-replication).

GENE EXPRESSION

Each ssDNA genome segment is monocistronic.

ENZYMES

REPLICATION

NUCLEAR

  1. Virus penetrates into the host cell.
  2. Uncoating, the viral ssDNA genome penetrates into the nucleus.
  3. The ssDNA is converted into dsDNA with the participation of cellular factors.
  4. Bidirectional dsDNA transcription from the IR promoter produces viral mRNAs and translation of viral proteins.
  5. Replication is initiated by cleavage of the (+)strand by REP, and occurs by rolling circle 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 CP and form virions that will be released in the extracellular space. c) be transported outside the nucleus, to a neighboring cell through plasmodesmata (cell-cell movement) with the help of viral movement proteins.

Host-virus interaction

Cell-cycle modulation

Nanovirus Clink protein is responsible for inhibiting host retinoblastoma protein and inducing transition from the G1 to S phase in preparation for virus replication since the virus targets differentiated non-dividing cells. .

Matching UniProtKB/Swiss-Prot entries

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

44 entries grouped by protein

6 entries

Capsid protein (CP) (Coat protein)

Select_allDeselect_all
CAPSD_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
CAPSD_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
CAPSD_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
CAPSD_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain
CAPSD_MDV9
Milk vetch dwarf virus (isolate 9) (MDV)
CAPSD_SCSVJ
Subterranean clover stunt virus (strain J) (SCSV)

4 entries

Cell cycle link protein (Clink)

Select_allDeselect_all
CLINK_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
CLINK_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
CLINK_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
CLINK_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

4 entries

Master replication protein (M-Rep) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-)

Select_allDeselect_all
MREP_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain

Master replication protein (M-Rep) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (ATP-dependent helicase C2) (Replication-associated protein 2) (Rep2)

MREP_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain

Master replication protein (M-Rep) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (ATP-dependent helicase C2) (Replication-associated protein 2) (Rep2)

MREP_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
MREP_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

4 entries

Putative movement protein (MP)

Select_allDeselect_all
MVP_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
MVP_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
MVP_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
MVP_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

4 entries

Putative nuclear shuttle protein

Select_allDeselect_all
NSP_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
NSP_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
NSP_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
NSP_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

3 entries

Para-Rep C1 (Rep1) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (ATP-dependent helicase C1) (Replication-associated protein of non-essential DNA C1)

Select_allDeselect_all
REP1_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
REP1_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
REP1_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain

Para-Rep C1 (Rep1) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (Replication-associated protein of non-essential DNA C1)

1 entry

Para-Rep C10 (Rep10) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (Replication-associated protein of non-essential DNA C10)

REP10_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain

2 entries

Para-Rep C2 (Rep2) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (Replication-associated protein of non-essential DNA C2)

Select_allDeselect_all
REP2_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
REP2_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

1 entry

Para-Rep C3 (Rep3) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (Replication-associated protein of non-essential DNA C3)

REP3_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain

1 entry

Para-Rep C6 (Rep6) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (Replication-associated protein of non-essential DNA C6)

REP6_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

2 entries

Para-Rep C7 (Rep7) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (ATP-dependent helicase C7) (Replication-associated protein of non-essential DNA C7)

Select_allDeselect_all
REP7_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
REP7_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain

2 entries

Para-Rep C9 (Rep9) (EC 2.7.7.-) (EC 3.1.21.-) (EC 3.6.1.-) (ATP-dependent helicase C9) (Replication-associated protein of non-essential DNA C9)

Select_allDeselect_all
REP9_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
REP9_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain

4 entries

Protein U1

Select_allDeselect_all
U1_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
U1_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
U1_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain
U1_SCSVF
Subterranean clover stunt virus (strain F) (SCSV) reference strain

3 entries

Protein U2

Select_allDeselect_all
U2_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
U2_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
U2_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain

3 entries

Protein U4

Select_allDeselect_all
U4_FBNY1
Faba bean necrotic yellows virus (isolate Egyptian EV1-93) (FBNYV) reference strain
U4_FBNY2
Faba bean necrotic yellows virus (isolate SV292-88) (FBNYV) reference strain
U4_MDV1
Milk vetch dwarf virus (isolate N) (MDV) reference strain