Chronic wasting disease is a prion disease of cervids (deer, elk, moose) that is potentially a threat to human health. A role for environmental prion contamination in transmission is supported by the finding that plants can take up prions from the soil and transmit them to animals. A concern is that prions of chronic wasting …
Satellites are subviral agents that differ from viroids because they depend on the presence of a helper virus for their propagation. Satellite viruses are particles that contain nucleic acid genomes encoding a structural protein that encapsidates the satellite genome. Satellite RNAs do not encode capsid protein, but are packaged by a protein encoded in the helper virus genome. Satellite …
Genomes of non-defective viruses range in size from 2,400,000 bp of dsDNA (Pandoravirus salinus) to 1,759 bp of ssDNA (porcine circovirus). Are even smaller viral genomes possible? The subviral agents called viroids provide an answer to this question. Viroids, the smallest known pathogens, are naked, circular, single-stranded RNA molecules that do not encode protein yet replicate …
Viroids, infectious agents that encode no proteins Read More »
On episode #272 of the science show This Week in Virology, the TWiV team describes aphid control by using a viral capsid protein to deliver a spider toxin to plants, and a human endogenous retrovirus that enhances expression of a neuronal gene. You can find TWiV #272 at www.microbe.tv/twiv.
On episode #271 of the science show This Week in Virology, the TWiV crew discusses two reports on viruses that might have crossed kingdoms, from plants to honeybees and from plants to vertebrates. You can find TWiV #271 at www.microbe.tv/twiv.
A consequence of the recent warm weather in the northeastern United States is the emergence of crocuses, an event that I documented at the TWiV Facebook page. A reader replied that it reminded her of the highly valued tulips with beautiful variegations produced by viruses. In 17th-century Holland patterned tulips such as the Semper Augustus (image) …
