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Related to Virion: viroid, prion


The complete, mature virus particle.



a mature virus particle or elementary virus corpuscle. A virion consists of nucleic acid (RNA or DNA), hereditary (genetic) material encased in a shell of protein subunits (molecules or aggregates of molecules). The virions of more complexly organized viruses may have external membranes (containing proteins, lipids, and carbohydrates) or special formations, as in bacteriophages.


Lwoff, A., R. Home, and P. Tournier. “A System of Viruses.” In Cold Spring Harbor Symposia on Quantitative Biology, vol. 27. New York, 1962. Pages 51-55.
References in periodicals archive ?
It has become routine to visualize the movement and progression of individual virions in cells, but the relevance of these observations was previously unclear, as many virions are defective or do not progress to make further copies of themselves.
Ultimately site directed mutagenesis in MSV was performed between lysine and valine in the CP region which was recorded as mutation of amino acid 182 and has been reported to affect the virion formation due to the absence of systemic infection.
Flavivirus infection is initiated when the viral RNA is introduced into the cytoplasm of the target cell after fusion of the virion envelope with endosomal membranes.
The holes on the surface of the polyhedra were not likely caused by the relocation of the virions in the process of sample preparation because these holes were not observed in viruses that underwent the same processes, including D.
iii) Late genes, which encode structural proteins of the capsid of the virion.
There are formed as a result of an accumulation of virions or viral components, although some inclussion bodies may not contain virions.
As a virion, the virus moves from plants to aphids, through aphids, and back into plants, and the topology of the virion guides the transmission process," Gray says.
The observed safety profile by antigen content indicated a higher local reactogenicity of alum-adjuvanted split virion formulations compared with non-adjuvanted split-virion formulations (point estimates have non overlapping 95% CIs).
Normally, APOBEC3G is encapsulated into progeny virions, where it remains nonfunctional until the virion infects its host cell.
The ordered processing suggests that a regulated cleavage cascade is needed for proper virion maturation and infectivity; mutations that either abrogate or alter the rate of cleavage of HIV Gag lead to the formation of aberrant, non-infectious particles [17,19].
James Cook along with articles on such topics as the structure and function of resistance proteins on solanaceous plants, a case study in virion and genome plasticity, mechanisms of disease resistance and susceptibility associated with cell walls, genome insights into the contribution of phytopathogenic bacterial plasmids to the evolutionary history of their hosts, the safety to cirus-resistance transgenic plants two decades after their introduction, virus-induced disease that alters host physiology, microarrays for quick identification of plant viruses, management of seed-borne bacterial diseases and challenges in tropical plant nematology.