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1

Reduced melanization after death in larvae of the confused flour beetle, Tribolium confusum, as a result of the irradiation treatment

100%

Ignatowicz S., Zaedee I. H.

Polskie Pismo Entomologiczne

|

1996

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tom 65

|

nr 1-2

2

Sclerotia of the acellular [true] slime mould Fuligo septica as a model to study melanization and anabiosis

84%

Krzywda A., Petelenz E., Michalczyk D., Plonka P. M.

Cellular and Molecular Biology Letters

|

2008

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tom 13

|

nr 1

130-143

Acellular (true) slime moulds (Myxomycetes) are capable of a transition to the stage of sclerotium — a dormant form of plasmodium produced under unfavourable environmental conditions. In this study, sclerotia of Fuligo septica were analyzed by means of electron paramagnetic resonance (EPR) spectroscopy. The moulds were cultivated in vitro on filter paper, fed with oat flour, and kept until the plasmodia began to produce sclerotia. The obtained sclerotia differed in colour from yellow through orange to dark-brown. The EPR spectra revealed a free radical, melanin-like signal correlated with the depth of the colour; it was strongest in the dark sclerotia. Sclerotization only took place when the plasmodia were starved and very slowly dried. Only the yellow sclerotia were able to regenerate into viable plasmodia. This suggests that myxomycete cytoplasm dehydration is an active process regulated metabolically. Plasmodial sclerotization may therefore serve as a convenient model system to study the regulation of cytoplasmatic water balance, and sclerotia as a convenient material for EPR measurements, combining the quality of plasmodia with the technical simplicity of the measurements characteristic of dry spores. Darkening of the sclerotia is most probably a pathological phenomenon connected with the impairment of water balance during sclerotization.

3

The effect of a small conotoxin-like ctx gene from Autographa californica nuclear polyhedrosis virus (AcMNPV) on insect hemolymph melanization

84%

Cao Q., Zhu S.-Y., Wu Y., Liu Y., Zhu J., Wang W.

Polish Journal of Microbiology

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2012

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tom 61

|

nr 3

The conotoxin-like (ctx) gene encodes a small cysteine-rich polypeptide in various baculoviruses. Previous research has demonstrated that the product of the ctx gene could be purified from insect cells infected by Autographa californica nuclear polyhedrosis virus (AcMNPV), but its function was unknown. In this paper, we compared the conserved cysteine motif structure (CX3GX2CX5CCX3CX6C) of the ctx gene in baculoviruses and generated recombinant Bombyx mori nuclear polyhedrosis virus (BmNPV) with the BmNPV bacmid system. !e recombinant BmNPV contained the ctx gene from AcMNPV or a fusion gene of ctx with eGFP, respectively. Fluorescence in CTX-eGFPpositive cells was mainly observed on the cell membrane. To gain insight into CTX function, two methods were used to elucidate the affect CTX had on hemolymph melanization in vivo and in vitro in insect larvae and pupae. The results indicated that CTX abrogates hemolymph melanization; however, the mechanisms require further evaluation.

4

Geographical variation in wing pattern in Phengaris (=Maculinea) arion (L.) (Lepidoptera: Lycaenidae): subspecific differentiation or clinal adaptation?

67%

Sielezniew M., Dziekanska I.

Annales Zoologici

|

2011

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tom 61

|

nr 4

Socially parasitic and globally threatened Phengaris (=Maculinea) arion (L.) is one of the most intensively investigated insect species in Europe. Although current studies focus on ecology and genetics, the butterfly has also attracted attention because of its morphology. An extremely variable black pattern on the blue background of the wing upperside has resulted in the description of many different forms or even subspecies. We studied the variation of 148 individuals from five regional populations at a latitudinal gradient in Poland: two north-eastern populations, one middle-eastern populations and two southern populations. A proportion of the area covered with marginal strips and spots was measured, and the presence/absence of particular elements was also analyzed. For all except one, the most northern region, we found significant sexual dimorphism, with females being darker than males. Within sexes, the melanization level was higher in the north-east than in the south, and the mid - eastern region showed intermediate characteristics. Differences in colouration overlapped with variation in host ant use, but neither feature corresponded with the available genetic data and therefore clinal variation is a more likely explanation for the observed pattern. Melanization level may be an adaptation to climatic conditions, but it remains unclear which strategy of dorsal basking is applied by P. arion.

5

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trans-Pro isosteres in the development of non-selective and selective mimetic agonists of insect pyrokinin neuropeptides: A review

67%

Nachman R. J.

Pestycydy

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2009

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nr 1-4

33-39

The pyrokinin (PK) family plays a multifunctional role in an array of important physiological processes in a variety of insects. A PK active core analog containing an (E)-alkene, transPro isosteric component was evaluated in five disparate PK bioassays and/or in a recombinant PK receptor cell line, representing six different insect species. The assays included pheromone biosynthesis in the moth Heliothis peltigera, melanization in the larval Spodoptera littoralis, pupariation acceleration in the larval fly Neobellieria bullata, diapause termination in the moth Heliothis zea, and hindgut contraction in the cockroach Leucophaea maderae. This constrained analog demonstrated unselective agonist activity that approached, matched, or exceeded the activity of parent PK peptides of equal length in all six PK assays. The results provide strong evidence for the orientation of Pro and the core conformation adopted by PK neuropeptides during interaction with disparate PK receptors. A PK active core analog incorporating a second transPro motif, the dihydroimidazoline moiety, was found to demonstrate pure, selective agonism in the melanotropic bioassay, with no significant activity in three other PK bioassays. Both types of transPro isosteric analogs feature modification adjacent to the primary tissue-bound peptidase hydrolysis site that is expected to enhance biostability over natural PK peptides. The research further identifies two novel scaffolds with which to design either selective or non-selective mimetic PK analogs as potential leads in the development of environmentally favorable pest management agents capable of disrupting PK-regulated systems.

6

Proces melanizacji ciala u napromieniowanych larw skorka zbozowego, Trogoderma granarium Ev.

67%

Banasik-Solgala K., Ignatowicz S.

Progress in Plant Protection

|

1997

|

tom 37

|

nr 2

50-53

7

Metoda identyfikacji napromieniowanych larw owadow dla potrzeb kwarantanny

67%

Banasik-Solgala K.

Progress in Plant Protection

|

1996

|

tom 36

|

nr 2

373-375

8

Melanization process in irradiated larvae of stored product moths

67%

Banasik-Solgala K., Ignatowicz S.

Polskie Pismo Entomologiczne

|

1997

|

tom 66

|

nr 1-2

9

Histopathology of Conidiobolus coronatus [Entomophthorales] infection in Galleria mellonella [Lepidoptera] larvae

67%

Bogus M. I., Szczepanik M.

Acta Parasitologica

|

2000

|

tom 45

|

nr 1

The histopathology of Conidiobolus coronatus infected Galleria mellonella larvae was investigated. In order to distinguish between morphological changes accompanying the dying process and changes connected with the activation of host-defense mechanisms, two fungal strains were used: A(+) killing 90-100% of Galleria larvae and A(-) causing 20-35% mortality in infected hosts. C. coronatus infection resulted in the appearance of black spots on the insect cuticle. Cross-sections revealed callosity and melanization of the cuticle at the infection site. Melanized epidermal cells together with the haemocytes accumulating beneath the place of infection formed a haemocytic capsule. Characteristic changes were observed in the Malpighian tubule morphology of insects surviving infection. Up to 60% of tubules inside survivor become brown, thick and fragile. Histological studies of the deformed tubules revealed the disappearance of the brush border and pycnosis of epithelial cell nuclei taking place at the time of termination of the exposure to the fungal pathogen. Twenty four hours later lumens of deformed Malpighian tubules were filled to capacity with a brown substance and surrounded by numerous layers of haemocytes forming a non-melanized nodule. All other organs of the infected Galleria larvae remained unchanged. No fungal structures were found inside the haemocoel and organs of the host larvae. The fat bodies of the survivors as well as of the dying insects were not changed and contained lipid droplets, suggesting that larval death was due to mycotoxin(s) produced by the pathogenic fungus Saprophytic development of C. coronatus was observed in the case of only one cadaver out of the 53 investigated.

Ograniczanie wyników

Reduced melanization after death in larvae of the confused flour beetle, Tribolium confusum, as a result of the irradiation treatment

Sclerotia of the acellular [true] slime mould Fuligo septica as a model to study melanization and anabiosis

The effect of a small conotoxin-like ctx gene from Autographa californica nuclear polyhedrosis virus (AcMNPV) on insect hemolymph melanization

Geographical variation in wing pattern in Phengaris (=Maculinea) arion (L.) (Lepidoptera: Lycaenidae): subspecific differentiation or clinal adaptation?

trans-Pro isosteres in the development of non-selective and selective mimetic agonists of insect pyrokinin neuropeptides: A review

Proces melanizacji ciala u napromieniowanych larw skorka zbozowego, Trogoderma granarium Ev.

Metoda identyfikacji napromieniowanych larw owadow dla potrzeb kwarantanny

Melanization process in irradiated larvae of stored product moths

Histopathology of Conidiobolus coronatus [Entomophthorales] infection in Galleria mellonella [Lepidoptera] larvae