Parasitism-Linked Block of Host Plasma Melanization

Shelby, Kent S.; Adeyeye, Olusola A.; Okot-Kotber, B. M.; Webb, Bruce A.

doi:10.1006/jipa.2000.4925

Cited by 80 publications

(58 citation statements)

References 26 publications

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“…CsIV, transmitted by C. sonorensis to its host H. virescens, is perhaps the best studied polydnavirus with respect to a role in the suppression of host melanization (Shelby and Webb, 1999;Shelby et al, 2000). In this system, CsIV infection causes a depression in the activity and titer of three enzymes of the melanization pathway, namely PO, dopachrome isomerase, and DOPA decarboxylase (DDC).…”

Section: Effect Of Triv Infection On Cf Ppo Transcript Accumulationmentioning

confidence: 99%

Prophenoloxidases 1 and 2 from the spruce budworm, Choristoneura fumiferana: Molecular cloning and assessment of transcriptional regulation by a polydnavirus

Doucet

Béliveau

Dowling

et al. 2008

Arch Insect Biochem Physiol

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Immune challenge in arthropods is frequently accompanied by melanization of the hemolymph, a reaction triggered by the activation of prophenoloxidase (PPO). Because their immature stages are spent inside the hemocoel of insect larvae, endoparasitoids have evolved strategies to escape or counter melanin formation. Very little molecular information is available on these endoparasitoid counterstrategies. We have sought to shed light on the inhibition of melanization in the spruce budworm, Choristoneura fumiferana, by the parasitic wasp Tranosema rostrale, by cloning two host PPO homologs and studying their transcriptional regulation after parasitization. The two polypeptides are encoded by transcripts of approximately 3.3 kb (for CfPPO1) and 3.0 kb (for CfPPO2) and possess structural features typical of other insect PPOs. While there appears to be a single CfPPO2 gene in the C. fumiferana genome, we detected three CfPPO1 mRNA variants displaying insertions/deletions in the 3' untranslated region, suggesting that there may be more than one CfPPO1 gene copy. Both CfPPO1 and CfPPO2 were expressed at high levels in C. fumiferana 6th instars, and parasitization by T. rostrale had no apparent impact on the level of their transcripts. Injection of a large dose (0.5 female-equivalent) of polydnavirus-laden calyx fluid extracted from T. rostrale, which is known to inhibit melanization in C. fumiferana, only caused a transient decrease in CfPPO1 and CfPPO2 transcript accumulation at 2-3 d post injection. It thus appears that transcriptional downregulation of C. fumiferana PPO by T. rostrale plays a minor role in the inhibition of hemolymph melanization in this host-parasitoid system.

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Section: Effect Of Triv Infection On Cf Ppo Transcript Accumulationmentioning

confidence: 99%

Prophenoloxidases 1 and 2 from the spruce budworm, Choristoneura fumiferana: Molecular cloning and assessment of transcriptional regulation by a polydnavirus

Doucet

Béliveau

Dowling

et al. 2008

Arch Insect Biochem Physiol

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“…Phenoloxidase enzyme plays an important role in nonself recognition and thereby confers immunity against exogenous chemicals, parasites, parasitoids and pathogens in various arthropods (Ratcliffe et al, 1984;Marmaras et al, 1996;Ashida and Brey, 1997;Shelby, 2000;Shiao et al, 2001;Mucklow and Ebert, 2003;Yu et al, 2003;Ling et al, 2005;Zhu et al, 2009). The lowest dose of the essential oil of the selected plants could not induce phenoloxidase activity in Antheraea assama larvae while the higher dosages significantly enhanced the enzyme activity than that of control larvae.…”

Section: Discussionmentioning

confidence: 99%

Effect of Plant Based Essential Oil on Immune Response of Silkworm, Antheraea assama Westwood (Lepidoptera: Saturniidae)

Khanikor¹,

Dipsikha²

2012

International Journal of Industrial Entomology

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Botanicals have been regarded as sustainable solution of pest control because of their nominal effect on nontarget pest, biodegradability and other environment friendly properties. However, study on impact of botanicals against beneficial insects is less. In this investigation effort has been made to study the effect of essential oils of Ocimum sanctum, Ocimum gratissimum and Ageratum conyzoides against non-mulberry silkworm Antheraea assama in terms of percent mortality, total haemocyte count (THC) and phenol oxidase (PO) enzyme activity. After application of essential oil of the plants by contact residual film technique, age dependent decrease of percent mortality was recorded. Topical treatment of oil at higher dosages (1 µlg -1 and 0.5 µlg -1 ) caused 100% mortality of late instar larvae at 24 hour but the lowest dose (0.25 µlg -1 ) did not cause any mortality till 48 hour of treatment. Initial increase of total haemocyte count (THC) was recorded at early hours of treatment (0.25 hour) at all dosages (1, 0.5, 0.25 µlg -1 ) after topical treatment. A dose dependent increase was observed in phenol oxidase enzyme activity and this might indicate ability of the essential oils to cause induction of immune response in Antheraea assama larvae.

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“…Campoletis sonorensis, obtained only during the first sampling (2014/2015), is a generalist endoparasitoid with high efficiency in the biological control of several moth pests, including the Americans Heliothinae as Chloridea virescens (Fabricius, 1777) and H. zea (SHELBY et al 2000). This wasp has been also mentioned parasitizing H. armigera in the Old World (FATHIPOUR & SEDARATIAN 2013).…”

Section: Department Of Zoology -Universidade De Brasília (Dzub) and mentioning

confidence: 99%

Parasitoides associados com Helicoverpa armigera em áreas de refúgio de algodão, no Oeste da Bahia, Brasil

et al. 2017

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Natural biological control is one of the major causes responsible for reduction of pest population in agricultural ecosystem. However, natural biological control importance is usually minimized by not being estimated. This study reports the occurrence of Campoletis sonorensis (Cameron, 1886) (Hymenoptera: Ichneumonidae), Archytas marmoratus (Townsend, 1915) and Archytas incertus (Macquart, 1851) (Diptera: Tachinidae) associated with Helicoverpa armigera (Hübner, 1809) (Lepidoptera: Noctuidae). The rate of larval parasitism was up to 41% in structured refuge areas of cotton, without chemical control with insecticides. This study strengthens our knowledge relating to parasitoids associated with natural control of H. armigera in the American continent. In addition, it documents the rule that structured refuge areas could play as a source of natural enemies, besides their contribution to production of non-selective populations to Bt technology.

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Parasitism-Linked Block of Host Plasma Melanization

Cited by 80 publications

References 26 publications

Prophenoloxidases 1 and 2 from the spruce budworm, Choristoneura fumiferana: Molecular cloning and assessment of transcriptional regulation by a polydnavirus

Prophenoloxidases 1 and 2 from the spruce budworm, Choristoneura fumiferana: Molecular cloning and assessment of transcriptional regulation by a polydnavirus

Effect of Plant Based Essential Oil on Immune Response of Silkworm, Antheraea assama Westwood (Lepidoptera: Saturniidae)

Parasitoides associados com Helicoverpa armigera em áreas de refúgio de algodão, no Oeste da Bahia, Brasil

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