Thaumetopoein, an urticating protein of the processionary hairs of the caterpillar (Thaumetopoea pityocampa Schiff) (Lepidoptera, Thaumetopoeidae)

The irritating fraction extracted from processionary caterpillar hairs contains soluble proteins which were separated by various electrophoretic and immuno-electrophoretic techniques. Some of these proteins are present also in cuticle and haemolymph. One protein of 28,000 daltons, formed of two subunits (13,000 and 15,000 daltons) is hair specific and causes a reaction in pig skin identical to that produced by hair extract. It is therefore an urticating protein and which we have named "Thaumetopoein".     

Birds as predators of the pine processionary moth (Lepidoptera: Notodontidae)

The beneficial role of insectivorous birds potentially contributing to the biological control of forest insect pests appears crucial in the context of climate warming, especially for species currently expanding their range such as the pine processionary moth Thaumetopoea pityocampa. Larvae of T. pityocampa are aposematic and carry true urticating setae which, together with overwintering in silk winter nests, prevent them from predation by most insectivorous forest birds. The present review aims at pointing out which bird species can regularly feed on this key forest defoliator throughout its distribution range, and which predation strategies allow birds to cope with the urticating setae carried by late-instar larvae. At least seven bird species can be considered as regular predators of the pine processionary moth: four large migrant specialists (great spotted cuckoo Clamator glandarius, common cuckoo Cuculus canorus, European nightjar Caprimulgus europaeus and Eurasian hoopoe Upupa epops) and three small sedentary generalists (great tit Parus major, crested tit Lophophanes cristatus and coal tit Periparus ater). Each species has developed morphological traits and foraging techniques to feed on different life stages of T. pityocampa throughout the year: (i) gizzard wall structure allowing the consumption of caterpillars with urticating setae (cuckoos); (ii) nocturnal foraging on moth imagos by aerial hawking (nightjars); (iii) ground probing on below-ground pupae with long curved bill (hoopoe); and (iv) shifted predation period in autumn and winter on eggs, early- and late-instar larvae, with particular feeding technique allowing to eat only the inner parts of urticating larvae stages (tits). Although several avian predators regularly feed on T. pityocampa, only a few specialist and generalist insectivorous birds may contribute to regulate its populations, especially when population density of the moth is low. Moreover, their efficiency may possibly be threatened by mismatches associated with climate change.     

Daily cycles for emission of urticating hairs from the pine processionary caterpillar (Thaumetopoea pityocampa S.) and the brown tail moth (Euproctis chrysorrhoea L) (Lepidoptera) in laboratory conditions

Summary In laboratory conditions, urticating hairs from the pine processionary caterpillar (Thaumetopoea pityocampa S.) and from the brown tail moth (Euproctis chrysorrhoea L.) are detectable in the air using an apparatus designed for the capture of airborne microorganisms and pollen research studies. The hairs produced by the caterpillars of these two species are distributed either via air currents or moths (only forEuproctis). Daily cycles of hair emission were observed and were in relation with locomotion and feeding activities of the caterpillars and with flying and reproductive activities of moths.     

The Role of Tactile and Chemical Stimuli in the Formation and Maintenance of the Processions of the Social Caterpillar Hylesia lineata (Lepidoptera: Saturniidae)

Colonies of the social caterpillar Hylesia lineata (Lepidoptera: Satumiidae) form long, single-file, head-to-tail processions as they move between their shelters and distant feeding sites. Although investigations of other processionary species have implicated a silk trail in the processionary process, silk plays little or no role in initiating or maintaining processions in H. lineata. Studies we report here implicate both tactile stimuli and a trail pheromone in the establishment and maintenance of processions. Processionaries elicit locomotion in the individual preceding them in line by brushing their heads against prominent sulci that project from the tips of their abdomens. Caterpillars mark their pathways with a pheromone deposited by brushing the ventral surfaces of their last abdominal segments against the substrate. The persistent pheromone is soluble in hexanes and appears to be secreted from glandular setae found on the proximal regions of the anal prolegs and the venter. In Y-choice tests, caterpillars selected newer trails over older trails and stronger trails over weaker trails. They did not distinguish between trials deposited by newly fed caterpillars and those deposited by starved caterpillars. Despite the unidirectional nature of processions, there is no indication that caterpillars can determine from the trail alone the direction in which the procession advanced. The significance of these findings to the foraging ecology of the caterpillars is discussed.     

Setae from Larvae of the Northern Processionary Moth (Thaumetopoea pinivora,TP) Stimulate Proliferation of Human Blood Lymphocytes In Vitro

Larvae of the Northern pine processionary moth (Thaumetopoea pinivora, TP) carry microscopic needles (setae), which by penetrating skin and mucous membranes, may cause inflammatory/immune derived symptoms in man. In the present study the stimulatory effects of setae on human blood lymphocytes in vitro was investigated. Blood mononuclear cells were separated from venous blood or buffy coat of ten healthy individuals, six previously exposed to setae and four with no known exposure. Lymphoproliferation was measured as uptake of ³H-thymidine. Setae were prepared from TP larvae. Setae and saline setae extracts stimulated proliferation of T-lymphocytes in the presence of monocytic cells. Stimulation was pronounced in cells from persons who had been exposed to setae, and weak in cells from non-exposed donors. Chitin also induced lymphocyte proliferation in most donors, but to a lesser extent and independently of donor''s previous exposure to setae. In conclusion, setae contain molecules that in the presence of monocytes activate human T-lymphocytes to proliferation. The antigenic nature of stimulatory molecules was supported by the significantly stronger lymphocyte response in persons previously exposed to setae than in non-exposed donors. The nature of such molecules remains to be defined.     

Etude ultrastructurale de la glande urticante de la chenille processionnaire du pin,Thaumetopoea pityocampa schiff. (Lepidoptere : Thaumetopoeidae)

The urticating gland of Thaumetopoea pityocampa, (Lepidoptera : Thaumetopoeidae) caterpillar is formed of only trichogen cells. These cells form an irregular cluster, which seems to be multilayered, although there is only one layer of cells. Each trichogen cell produces urticating protein (thaumetopoein), forms urticating hair, and the thin cuticle in which the hair is implanted.     

Pine processionary moth (Thaumetopoea pityocampa,Lepidoptera: Thaumetopoeidae) larvae are highly susceptible to the entomopathogenic fungi Metarhizium brunneum and Beauveria bassiana

The larvae of the pine processionary moth (PPM), Thaumetopoea pityocampa, feed on the needles of pine and cedar. The urticating hairs of older instars pose a threat to human and animal health. Strains of the entomopathogenic fungi, Metarhizium brunneum (V275, ARSEF 4556) and Beauveria bassiana (KTU-24), were assayed against first to fourth instar T. pityocampa using doses ranging from 1?×?10⁵ to 1?×?10⁸ conidia mL^?1. The three strains differed slightly in their virulence but caused 100% mortality of all instars at the highest dose. The newly emerged or first instar larvae were extremely susceptible with 100% mortality being achieved 2–4 days post inoculation with V275 at all but the lowest dose. The fourth instar larvae appeared to be less susceptible than earlier instars. There was good horizontal transmission of conidia from treated to un-inoculated larvae. However, mortality was higher in third and fourth instars and where the ratio of inoculated versus untreated larvae was high. This we presume is due to spores being more readily trapped by the urticating hairs found on third and older instar larvae. Injection of the nests offers a simple and environmentally friendly way of controlling the pest with reduced risk to operators.     

The brown-tail moth of Bombyx Euproctis chrysorrhoea L. (Lepidoptera) responsible for lepidopterism in France: biological interpretation

A scanning electron microscope study has enabled an explanation as to why the brown-tail moth provokes Lepidopterism. The brown-tail moth only provokes Lepidopterism via a transmission of the urticating hairs of its caterpillar. Urticating moths (genus Hylesia and Anaphae) protect their eggs and young caterpillars with urticating hairs, thus it is very ambiguous to label erucism as the contact dermatitis produced by caterpillar production or Lepidopterism as the contact dermatitis caused by moth urticating hairs.     

褐边绿刺蛾幼虫刺毛结构及蛰伤机制初探

刺蛾科幼虫是我国常见的农林业害虫之一,其体表长有防御性的有毒刺毛,会伤害接触者,使其产生瘙痒、刺痛、丘疹、红肿、皮炎等症状.本研究利用体视显微镜、扫描电镜对褐边绿刺蛾Parasa consocia末龄幼虫的刺毛形态结构进行了观察,将不同刺毛提取物进行小鼠足底皮下注射,测试刺激活性,并使用SDS-PAGE电泳对提取物成分...     

Atmospheric pollution of animal origin: the urticating hairs of the processionary caterpillar (Thaumetopoea pityocampa Schiff.) (Insects, Lepidoptera)

Urticating hairs of pine processionary caterpillars are detectable in air using techniques designed for airborne microorganisms and pollen's research. As with pollens, abondance of hairs is correlated with distance of production zone and with local meterological conditions. Collected in Bordeaux, urticating hairs will be considered for allergists as pollens and other allergic particles.     

Dispersion of the bio-aerosol produced by the oak processionary moth

The oak processionary moth (Thaumetopoea processionea L.) is found in oak forests in most European countries. The caterpillars bear urticating hairs (setae) as a chemical defence. These hairs break off and are small enough to become airborne and be transported by the wind. Upon contact with humans the toxin can cause an allergic reaction that ranges from a skin rash to respiratory distress. In order to measure the terminal settling velocity of this bioaerosol, we used a small elutriator and tested its functionality with particles of known aerodynamic diameter. We determined that the mean settling velocity of the setae is about 1 cm/s, corresponding to an aerodynamic diameter of 19 μm for setae with a diameter of 6 μm and a length of 190 μm. The dispersion of the hairs in the atmosphere for a typical summer day was calculated by means of an Eulerian model. The results of this calculation revealed that the maximum concentrations in the atmosphere on a typical summer day reach 20–30% of the concentration found directly at the source. Those maximum concentrations are reached at a distance from the source that varies between 174 and 562 m, depending on the atmospheric stability and the settling velocity.

Host and Phenology Shifts in the Evolution of the Social Moth Genus Thaumetopoea

The genus Thaumetopoea contains the processionary moths, a group of lepidopteran associated with forest trees, well known for the social behaviour of the larvae and for carrying urticating setae. The taxonomy of the genus is partly unresolved and a phylogenetic approach is lacking. The goal of this work is to produce a phylogeny for Thaumetopoea and to identify the main traits driving the evolution of this group. Eighteen mitochondrial and three nuclear genes were fully/partly sequenced. Markers were aligned and analysed singularly or in various combinations. Phylogenetic analyses were performed according to maximum likelihood and Bayesian inference methods. Trees obtained from largest data sets provided identical topologies that received strong statistical support. Three main clades were identified within Thaumetopoea and were further supported by several signatures located in the mitochondrial tRNAs and intergenic spacers. The reference topology was used to investigate the evolution of life history traits related to biogeography, host plant, ecology, and morphology. A multigenic approach allowed to produce a robust phylogenetic analysis of the genus Thaumetopoea, with the identification of three major clades linked to different ecological and life history traits. The first clade is associated with Angiosperm host plants and has a fast spring development of larvae on young foliage. The other clades have originated by one event of host plant shift to Gymnosperm Pinaceae, which implied a longer larval developmental time due to the lower nutritional quality of leaves. These clades showed different adaptations to such a constraint, the first with a switch of larval feeding to cold season (winter pine processionary moths), and the second with a retraction to high altitude and latitude and a development cycle extended over two years (summer pine processionary moths). Recent global warming is affecting all species and seems able to further shape the evolution of the group.     

Herbivory and climatic warming: a Mediterranean outbreaking caterpillar attacks a relict, boreal pine species

Climate change can harm many species by disrupting existing interactions or by favouring new ones. This study analyses the foreseeable consequences of climatic warming in the distribution and dynamics of a Mediterranean pest that causes severe defoliation, the pine processionary caterpillar Thaumetopoea pityocampa, and the effects upon the relict Andalusian Scots pine Pinus sylvestris nevadensis in the Sierra Nevada mountains (southeastern Spain). We correlated a set of regional data of infestation by T. pityocampa upon Scots pine, from a broad ecological gradient, with climatic data for the period 1991–2001, characterized by alternating warm and cold winters. Defoliation intensity shows a significant association with previous warm winters, implying that climatic warming will intensify the interaction between the pest and the Scots pine. The homogeneous structure of the afforested pine woodlands favours the outbreak capacity of the newcomer, promoting this new interaction between a Mediterranean caterpillar pest and a boreal tree at its southern distribution limit.     

Early leaf miners and the ground plan of the lepidopteran larval trunk: Caterpillar morphology of the basal moths Heterobathmia,Eriocrania, and Acanthopteroctetes

The larval trunk morphology including chaetotaxy, locomotory structures, and trunk musculature of Heterobathmia pseuderiocrania, Eriocrania cicatricella, and Acanthopteroctetes unifascia is described using conventional light, polarization, and scanning electron microscopy. The ground plan morphology of the lepidopteran larva and neolepidopteran caterpillar is discussed in light of the life history succession from free soil dwelling organism to endophagous and finally to a primarily free living, angiosperm associated organism. I suggest that the larval morphology is argued to be strongly influenced by the shift in number of surfaces present in the larval environment. Especially the environment of the endophagous species, where the upper surface of the leaf mine is linked to the presence of dorsal locomotory structures such as the retractable calli and dorsal friction patches is proposed to have had a significant impact on the morphology and locomotory mechnism of the lepidopteran caterpillar. The chaetotaxy of the lepidopteran ground plan is found to be simple, consisting only of primary and secondary tactile setae and segmental proprioceptors. The presumption of Gerasimov ([1935] Zool Anz 112:177–194) that MXD1 of the prothorax is a shifted mesothoracic MD setae is supported. I suggest that the serial arrangement of the proprioceptors MD1, present on all trunk segments except the prothorax, and a trisetous MV group on all the thoracic segments is part of the lepidopteran larval ground plan. The absence of apodeme structures associated with trunk musculature in the nonglossatans suggests that this is an autapomorphic character of the Lepidoptera and it is further found to have been influential in the evolution of the typical caterpillar trunk. The attachments of the thoracic muscles directly to the trunk integument, suggest that the apodemal structures ancestral to the Amphiesmenoptera have been reduced in the Lepidoptera. Within the non‐Neolepidoptera, the lifehistory shift may have resulted in reduction of the dorsal locomotory structures, such as calli. The abdominal musculature and structural similarities further suggest that the ventral calli are structural predecessors to the crotchet bearing proleg of the “typical caterpillar.” J. Morphol. 274:1239–1262, 2013. © 2013 Wiley Periodicals, Inc.     

Susceptibility of the pine processionary caterpillar Thaumetopoea pityocampa (Lepidoptera: Thaumetopoeidae) toward δ-endotoxins of Bacillus thuringiensis under laboratory conditions

A series of natural crystal proteins from B. thuringiensis subsp. Alesti 12–25, caucasicus, galleriae 11–67, galleriae 6–96, kenyae, and shondungensis and spore‐crystal preparations from finitimus 11–66 and from a recombinant strain of B. thuringiensis subsp. kurstaki expressing Cry 1 Ga1 only, were assessed as a toxic agent for the pine processionary caterpillar, Thaumetopoea pityocampa. Some preparations had a thoroughly investigated composition and contained Cry1Aa, Cry1Ab2, Cry1Ab7, Cry1D, Cry1F, Cry 1 Ga1, Cry9Aa, Cry26 crystal proteins, whereas crystals of B. thuringiensis subsp. caucasicus, kenyae, and shondungensis harboured predominantly unidentified toxins distant from commonly used prototypes. Bioassays were based on the simultaneous assignment of each treatment to groups of 20 full sibling first‐instar larvae, obtained from broods of a population from North‐western Italy. The toxin was applied to pine needles by the leaf dipping method and the effect was registered in both feeding inhibition and mortality. B. thuringiensis subsp. caucasicus, kenyae, galleriae 6–96, alesti, and galleriae 11–67 gave the best results in terms of both feeding inhibition and larval mortality. Broods tested in B. thuringiensis bioassays showed a substantial variation in susceptibility to the toxins, suggesting the potential development of resistance in the population.     

Foetal loss in dairy goats: function of the adrenal glands, corpus luteum and the foetal-placental unit.

To investigate the causes and mechanisms of foetal loss in Norwegian dairy goats, blood parameters in 40 goats that lost foetuses were compared with those in 40 goats that experienced a normal pregnancy. High mean levels of 15-ketodihydro-PGF2alpha, and low mean levels of oestrone sulphate throughout pregnancy were associated with foetal loss. The mean oestrone sulphate level was low before abortion, and the distinct peak that occurred at parturition in the control goats was not observed in connection with abortion. Association of other blood parameters with foetal loss was not detected. Infectious agents and toxins did not appear to be major causes of foetal loss in this study. The normal level of progesterone and cortisol in goats with foetal loss indicated that the function of the corpus luteum and adrenal glands, respectively, were not disturbed. The rapid decline in progesterone level associated with foetal loss may therefore be a result, rather than the cause, of foetal death. The lowered level of oestrone sulphate and elevated level of 15-ketodihydro-PGF2alpha in goats with foetal loss clearly indicated that the endocrine foetal-placental function was disturbed.     

The urticating setae of Ochrogaster lunifer,an Australian processionary caterpillar of veterinary importance

The bag‐shelter moth, Ochrogaster lunifer Herrich‐Schaffer (Lepidoptera: Notodontidae), is associated with a condition called equine amnionitis and fetal loss (EAFL) on horse farms in Australia. Setal fragments from O. lunifer larvae have been identified in the placentas of experimentally aborted fetuses and their dams, and in clinical abortions. The gregarious larvae build silken nests in which large numbers cohabit over spring, summer and autumn. The final instars disperse to pupation sites in the ground where they overwinter. Field‐collected O. lunifer larvae, their nests and nearby soil were examined using light and electron microscopy to identify setae likely to cause EAFL and to determine where and how many were present. Microtrichia, barbed hairs and true setae were found on the exoskeletons of the larvae. True setae matching the majority of setal fragments described from equine tissue were found on third to eighth instar larvae or exuviae. The number of true setae increased with the age of the larva; eighth instars carried around 2.0–2.5 million true setae. The exuvia of the pre‐pupal instar was incorporated into the pupal chamber. The major sources of setae are likely to be nests, dispersing pre‐pupal larvae and their exuviae, and pupal chambers.     

Proteomic analysis of the peritrophic matrix from the gut of the caterpillar, Helicoverpa armigera

The peritrophic matrix from the midgut of the caterpillar, Helicovera armigera, was solubilized by treatment with anhydrous trifluoromethanesulfonic acid, apparently by depolymerisation of its chitin component. This allowed the efficient extraction of proteins in a technique that may be broadly applicable to the analysis of other structures containing chitin. Gel electrophoresis and mass spectrometry of tryptic peptides were used to identify the extracted proteins with gut-expressed cDNA sequences. The major proteins of this cohesive, digestion-resistant structure are chitin deacetylase-like and mucin-like proteins, the latter with multiple chitin-binding domains that may cross-link chitin fibrils to provide a barrier against abrasive food particles and parasites, one of the major functions of the matrix. Other proteins found in the H. armigera gut peritrophic matrix suggest that the matrix is a dynamic, complex structure that may participate in the immobilization of digestive enzymes, actively protect the gut from parasite invasion and intercept toxins such as lectins and Bacillus thuringiensis crystal proteins.     

Beyond preference and performance: host plant selection by monarch butterflies,Danaus plexippus

The connection between adult preferences and offspring performance is a long‐standing issue in understanding the evolutionary and ecological forces that dictate host associations and specialization in herbivorous insects. Indeed, decisions made by females about where to lay their eggs have direct consequences for fitness and are influenced by interacting factors including offspring performance, defence and competition. Nonetheless, in addition to these attributes of the offspring, a female's choices may be affected by her own prior experience. Here we examined oviposition preference, larval performance and the role of learning in the monarch butterfly, Danaus plexippus, which encounters diverse milkweed host species across its broad range and over the course of migration. Monarch females consistently preferred to oviposit on Asclepias incarnata subspecies pulchra. This plant, however, was associated with poor caterpillar growth, low sequestration of toxins and the highest plant defences (latex and trichomes). We examined flexibility in this apparently maladaptive preference by testing the impact of previous experience and competition on preference. Experience laying on an alternative plant species enhanced preference for that species in contrast to A. i. pulchra. In addition, presence of a (competing) conspecific caterpillar on A. i. pulchra had a strongly deterrent effect and reversed host plant preferences. Thus, monarch butterflies exhibit preferences contrary to what would be expected based on offspring development and sequestered defences, but their preferences are altered by learning and competition, which may allow butterflies to shift preferences as they encounter diverse milkweeds across the landscape. Learning and perception of threats (i.e. competition or predation) may be critical for most herbivorous insects, which universally experience heterogeneity among their potential host plants.     

The influence of bacterial toxins on the carcinogenesis

Bacterial infections may constitute an important risk factor of developing cancer disease. Molecular mechanisms by which bacteria contribute to cancer are extremely complex and still remain not fully understood. So far, it is generally accepted that Helicobacter pylori infections are associated with induction of gastric adenocarcinoma and MALT lymphoma. Two H. pylori toxins which modulate many cellular functions are VacA and CagA. So far, CagA is the only one known bacterial oncoprotein. However, many other bacteria produce toxins or effector proteins perturbing host cell homeostasis or/and evoking chronic inflammation. Both processes may be associated with tumour formation. Bacterial toxins which interfere, with various host signal transduction pathways, deregulate processes of cell division, proliferation and differentiation and modulate apoptosis. Some toxins cause even direct DNA damage. This review discuss the potential links between action of bacterial toxins and cancer.