Possible role of teratocytes of the gregarious parasitoid,Cotesia ( =Apanteles)glomerata in the suppression of phenoloxidase activity in the larval host,Pieris rapae crucivora

1990 ◽  
Vol 13 (3-4) ◽  
pp. 177-185 ◽  
Author(s):  
Hideo Kitano ◽  
Haruhisa Wago ◽  
T?ru Arakawa
Keyword(s):  
Pieris Rapae ◽  
Phenoloxidase Activity ◽  
Larval Host ◽  
Pieris Rapae Crucivora ◽  
Gregarious Parasitoid

scholarly journals The impact of host aggressiveness on sex allocation by the gregarious parasitoid wasp Cotesia glomerata (L.)

2009 ◽  
Vol 5 (2) ◽  
pp. 197-199 ◽  
Author(s):  
Shingo Tanaka
Keyword(s):  
Sex Allocation ◽  
Pieris Rapae ◽  
Parasitoid Wasp ◽  
Pieris Brassicae ◽  
Cotesia Glomerata ◽  
Physiological Status ◽  
Male Ratio ◽  
Pieris Rapae Crucivora ◽  
Gregarious Parasitoid ◽  
The Impact

Parasitoid wasps lay female eggs or a high proportion of female eggs in favourable host insects because female wasps require many more resources during their development. Many studies have tested the effects of host physiological status on the sex allocation of parasitoids, but few have attempted to test the effects of host behavioural traits. Cotesia glomerata is a gregarious parasitoid wasp that lays eggs in caterpillars of pierid butterflies. The brood sex ratio in C. glomerata females that attacked aggressive host caterpillars was compared with that in females that attacked less aggressive hosts. The male ratio was higher when C. glomerata attacked aggressive Pieris brassicae caterpillars than when it attacked less aggressive Pieris rapae crucivora caterpillars. However, when C. glomerata females were induced to oviposit in anaesthetized P. brassicae caterpillars, the male ratio in their offspring was significantly lower than when they attacked unanaesthetized caterpillars. C. glomerata was attacked by aggressive host caterpillars during oviposition bouts. It is likely that this aggressive host behaviour disturbed the fertilization process in ovipositing C. glomerata females. These results suggest that a behavioural defence by host caterpillars affects sex allocation in the parasitoid wasp C. glomerata .

scholarly journals Thioester-Containing Protein-4 Regulates the Drosophila Immune Signaling and Function against the Pathogen Photorhabdus

2016 ◽  
Vol 9 (1) ◽  
pp. 83-93 ◽  
Author(s):  
Upasana Shokal ◽  
Ioannis Eleftherianos
Keyword(s):  
Immune Response ◽  
Photorhabdus Luminescens ◽  
Human Pathogen ◽  
Loss Of Function ◽  
Phenoloxidase Activity ◽  
Microbial Infections ◽  
Immune Pathways ◽  
And Function ◽  
Important Progress

Despite important progress in identifying the molecules that participate in the immune response of Drosophila melanogaster to microbial infections, the involvement of thioester-containing proteins (TEPs) in the antibacterial immunity of the fly is not fully clarified. Previous studies mostly focused on identifying the function of TEP2, TEP3 and TEP6 molecules in the D. melanogaster immune system. Here, we investigated the role of TEP4 in the regulation and function of D. melanogaster host defense against 2 virulent pathogens from the genus Photorhabdus, i.e. the insect pathogenic bacterium Photorhabdus luminescens and the emerging human pathogen P. asymbiotica. We demonstrate that Tep4 is strongly upregulated in adult flies following the injection of Photorhabdus bacteria. We also show that Tep4 loss-of-function mutants are resistant to P. luminescens but not to P. asymbiotica infection. In addition, we find that inactivation of Tep4 results in the upregulation of the Toll and Imd immune pathways, and the downregulation of the Jak/Stat and Jnk pathways upon Photorhabdus infection. We document that loss of Tep4 promotes melanization and phenoloxidase activity in the mutant flies infected with Photorhabdus. Together, these findings generate novel insights into the immune role of TEP4 as a regulator and effector of the D. melanogaster antibacterial immune response.

scholarly journals Abscisic acid is essential for rewiring of jasmonic acid-dependent defenses during herbivory

2019 ◽  
Author(s):  
Irene A Vos ◽  
Adriaan Verhage ◽  
Lewis G Watt ◽  
Ido Vlaardingerbroek ◽  
Robert C Schuurink ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Jasmonic Acid ◽  
Plant Hormone ◽  
Pieris Rapae ◽  
Necrotrophic Pathogen ◽  
Plant Insect Interactions ◽  
Gcc Box ◽  
Insect Interactions ◽  
And Control

AbstractJasmonic acid (JA) is an important plant hormone in the regulation of defenses against chewing herbivores and necrotrophic pathogens. In Arabidopsis thaliana, the JA response pathway consists of two antagonistic branches that are regulated by MYC- and ERF-type transcription factors, respectively. The role of abscisic acid (ABA) and ethylene (ET) in the molecular regulation of the MYC/ERF antagonism during plant-insect interactions is still unclear. Here, we show that production of ABA induced in response to leaf-chewing Pieris rapae caterpillars is required for both the activation of the MYC-branch and the suppression of the ERF-branch during herbivory. Exogenous application of ABA suppressed ectopic ERF-mediated PDF1.2 expression in 35S::ORA59 plants. Moreover, the GCC-box promoter motif, which is required for JA/ET-induced activation of the ERF-branch genes ORA59 and PDF1.2, was targeted by ABA. Application of gaseous ET counteracted activation of the MYC-branch and repression of the ERF-branch by P. rapae, but infection with the ET-inducing necrotrophic pathogen Botrytis cinerea did not. Accordingly, P. rapae performed equally well on B. cinerea-infected and control plants, whereas activation of the MYC-branch resulted in reduced caterpillar performance. Together, these data indicate that upon feeding by P. rapae, ABA is essential for activating the MYC-branch and suppressing the ERF-branch of the JA pathway, which maximizes defense against caterpillars.

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