Caulimoviridae

VIRION

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Virions not enveloped, bacilliform (30 x 60-900 nm) or isometric (45-50 nm in diameter).

GENOME

Monopartite, open circular, double stranded DNA of 7000-8200 base pairs with discontinuities in both strands: one in the transcribed strand and one to three in the non-transcribed strand. Encode for 1 to 8 proteins.

GENE EXPRESSION

REPLICATION

CYTOPLASMIC / NUCLEAR

  1. Attachment of the viral proteins to host receptors mediates its entry into the host cell.
  2. The viral dsDNA is released into the nucleus where it is transcribed by host RNA polymerase II
  3. RNA translation produces viral proteins.
  4. Genomic RNA is retrotranscribed in the cytoplasm into new dsDNA genomes
  5. Genomes are encapsidated with capsid protein, releasing new virions.