Non-enveloped, flexuous, filamentous, of 760nm lengths x 12-15 nm in diameter with helical symmetry.


Monopartite, linear, ssRNA(+) genome about 8.3kb in size. 3' terminus has a poly (A) tract. 5' terminus has a genome-linked protein (VPg).


The virion RNA is infectious and serves as both the genome and viral messenger RNA. The genomic RNA is translated into polyprotein subsequently processed into functional products.

Cleavage sites in the family Potyviridae



  1. Virus penetrates into the host cell.
  2. Uncoating, and release of the viral genomic RNA into the cytoplasm.
  3. The viral RNA is translated to produce a polyprotein which is into the RdRp protein and structural proteins.
  4. Replication takes place in cytoplasmic viral factories. A dsRNA genome is synthesized from the genomic ssRNA(+).
  5. The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA(+) genomes.
  6. Virus assembly in the cytoplasm.
  7. Viral movement protein P3N-PIPO probably mediates virion cell-to-cell transfer.