From MicrobeWiki, the student-edited microbiology resource
A Viral Biorealm page on the genus Potyvirus
Higher order taxa
Viruses; ssRNA positive-strand viruses, no DNA stage; Potyviridae; Potyvirus
Alpinia mosaic virus, Bean yellow mosaic virus, Papaya ringspot virus, Tobacco vein mottling virus (Examples)
Description and Significance
Potyviruses are the major genus in the Potyviridae family and infect a broad range of host plants, both monocots and dicots, in most climatic regions. These viruses can be responsible for severe economic damage to crops.
The genome of potyvirus is monopartite and only one particle size of linear, positive-sense single-stranded RNA is recovered. The genome is sequenced and the complete sequence is about 9000-10080-12000 nucleotides long. The genome has a base ratio of 21-23.51-26 % guanine; 23-30.15-44% adenine; 14.9-22.41-28% cytosine; 15.6-24.41-30.9% uracil. The 5'-end of the genome has a genome-linked protein (VPg). The 3'-terminus has a poly (A) tract and the genome has an intergenic poly (A) region. (source: ICTV dB Descriptions)
Virion Structure of a Potyvirus
The virions of a potyvirus consist of a non-enveloped capsid. The capsid is elongated with helical symmetry. The capsid is filamentous, flexuous with a length of 680-900 nm and a width of 11-13 nm. The axial canal can be distinct or indistinct but 2-2.5-3 nm in diameter. The basic helix is obvious or obscure and the pitch of the helix is 3.3-3.38-3.4 nm. (source: ICTV dB Descriptions)
Reproduction Cycle of a Potyvirus in a Host Cell
The genome replicates in the cytoplasm. The sub-genomic RNA is absent from infected cells during transcription. Virions may provide helper functions to dependent virus during replication. The virion acts a helper for another virus.
Viral Ecology & Pathology
Potyviruses are transmited predominantly by aphids in a non-persistent manner.
Silvio Urcuqui-Inchima, Anne-Lise Haenni, Francoise Bernardi; "Potyvirus proteins: a wealth of functions"; Virus Research 74; 2001