Journal of Insect Science (2006) 6 (46), 48-49

H.J.R. Popham (2006)
Antiviral response in Heliothis virescens
Journal of Insect Science 6 (46), 48-49
in M. Adams et al. [editors] Abstracts of the Fifth International Symposium on Molecular Insect Science (May 20-24, 2006, Tucson, Arizona USA), 76 pp.
Abstract: Lepidopteran larvae are known to resist baculovirus infection by the selective apoptosis of infected midgut epithelial cells, and by the sloughing off of infected cells from the midgut. Once the infection breaches the midgut epithelial barrier and propagates from infective foci to the hemocoel however, there are few known mechanisms to account for the resistance and clearance of infection observed in some virus/host combinations. Utilizing an in vitro assay, Heliothis virescens larval plasma was found to contain high levels of an antiviral activity against Helicoverpa zea single nucleopolyhedrovirus (HzSNPV) budded virus. The innate factor responsible for the virucidal effect was identified as phenoloxidase. To elucidate the contributions of phenoloxidase to the innate immune response against baculovirus infection, specific inhibitors were employed. In vitro the general inhibitors of melanization (N-acetyl cysteine, ascorbate and glutathione), and specific inhibitors of phenoloxidase (phenylthiourea, and Kojic acid), completely blocked virucidal activity up to the level seen in controls. Addition of the enzyme catalase to plasma did not affect virucidal activity; however addition of superoxide dismutase exhibited a modest inhibitory effect. Inhibitors of nitric oxide synthase activity did not affect virucidal activity. Beyond innate virucidal activity, proteins induced by viral infection were also studied. Using two dimensional difference gel electrophoresis (DIGE, Amersham), protein expression was compared between plasma from uninfected and infected larvae. Preliminary results of this study will be presented.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Holly J.R. Popham

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
resistance/tolerance/defence of host
molecular biology - genes

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Heliothis virescens
Helicoverpa zea single nucleopolyhedrovirus (entomopathogen)	Heliothis virescens