title: The involvement of a helper component in nonpersistent transmission of plant viruses by aphids.
abstract: Certain plant viruses require a 'helper component' in order to be transmitted by aphids. The helper component for potyviruses is a virus-encoded protein with a subunit molecular weight of between 50,000 and 60,000. Aphid transmission of caulimoviruses is associated with the presence of an 18,000 molecular weight polypeptide. The mode of action of the helper component is the subject of speculation.
mesh_terms: D000818:Animals; D001042:Aphids / Q000382:microbiology*; D006378:Helper Viruses / Q000302:isolation & purification*; D007303:Insect Vectors; D010935:Plant Diseases; D010942:Plant Viruses / Q000302:isolation & purification*