Tetraparvovirus (taxid:1511911)

VIRION

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Non-enveloped, round, T=1 icosahedral symmetry, 18-26 nm in diameter. The capsid consists of 60 copies of CP protein.
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GENOME

Linear, ssDNA genome of about 4 to 6 kb in size. Both positive and negative strands are encapsidated, although the percentage of particles encapsidating the positive strand can be lower depending on the host cell. ORFs for both the structural and non-structural proteins are located on the same DNA strand.
The genome is replicated through rolling-hairpin mechanism.

GENE EXPRESSION

Host proteins transcribe the genomes into mRNAs. Alternative splicing allows expression of both structural and non-structural proteins.

ENZYMES

REPLICATION

NUCLEAR

  1. Attachement to host receptors initiates clathrin-mediated endocytosis of the virion into the host cell.
  2. The virion penetrates into the cytoplasm via permeabilization of host endosomal membrane.
  3. Microtubular transport of the virion toward the nucleus.
  4. The viral ssDNA genome penetrates into the nucleus.
  5. The ssDNA is converted into dsDNA by cellular proteins.
  6. dsDNA transcription gives rise to viral mRNAs when host cell enters S phase and translated to produce viral proteins.
  7. Replication occurs through rolling-hairpin mechanism, with NS1 endonuclease binding covalently to the 5' genomic end.
  8. Individual ssDNA genomes are excised from replication concatemers by a process called junction resolution.
  9. These newly synthesized ssDNA can either
    a) be converted to dsDNA and serve as a template for transcription/replication
    b) be encapsidated to form new virions that are released by cell lysis.

Host-virus interaction

These structures were created with the help of Colabfold by Jason Nomburg, Nathan Price and Jennifer Doudna (ModelArchive).

Human parvovirus 4 G1 taxid:1511919

Protein ModelArchive
ORF1 ma-jd-viral-23474
ORF2 ma-jd-viral-41330

Porcine parvovirus 2 taxid:1126383

Protein ModelArchive
Non-structural protein ma-jd-viral-23471
Structural protein CDS ma-jd-viral-41344

Tetraparvovirus sp. taxid:1908804

Protein ModelArchive
NS1 ma-jd-viral-23470
VP1 ma-jd-viral-41331

Tetraparvovirus ungulate1 taxid:3052771

Protein ModelArchive
Major structural protein ma-jd-viral-07322
Minor structural protein ma-jd-viral-41354
Nonstructural protein ma-jd-viral-23468