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tissue-specific expression and silencing phenotypes of mitochondrial phosphate carrier paralogues in several insect species.the mitochondrial phosphate carrier gene (pic) encodes a membrane protein that mediates the supply of inorganic phosphate from the cytosol into the mitochondrial matrix. this substrate-specific transport system plays an important role in efficient atp synthesis. mammals appear to have only one pic with two alternative splicing variants whose functional differences remain unclear. the present study is the first to characterize the multiple genes that encode pic in insects. bombyx mori was found t ...201728224717
ontogeny of pioneer neurons in the antennal nervous system of the grasshopper schistocerca gregaria.the nervous system of the antenna of the grasshopper schistocerca gregaria consists of two nerve tracts in which sensory cells project their axons to the brain. each tract is pioneered early in embryogenesis by a pair of identified cells located apically in the antennal lumen. the pioneers are thought to originate in the epithelium of the antenna and then delaminate into the lumen where they commence axogenesis. however, unambiguous molecular identification of these cells in the epithelium, of a ...201727833997
biomechanical factors in the adaptations of insect tibia cuticle.insects are among the most diverse groups of animals on earth. their cuticle exoskeletons vary greatly in terms of size and shape, and are subjected to different applied forces during daily activities. we investigated the biomechanics of the tibiae of three different insect species: the desert locust (schistocerca gregaria), american cockroach (periplaneta americana) and death's head cockroach (blaberus discoidalis). in a previous work, we showed that these tibiae vary not only in geometry (leng ...201627486904
identification and characterization of two "sensory neuron membrane proteins" (snmps) of the desert locust, schistocerca gregaria (orthoptera: acrididae).pheromone-responsive neurons of insects not only require specific receptors but in addition several auxiliary components, including the "sensory neuron membrane protein," snmp. accordingly, snmp is considered as a marker for neurons responding to pheromones. for the desert locust schistocerca gregaria, it is known that the behavior, including aggregation behavior and courtship inhibition, is largely controlled by pheromones. however, little is known about pheromones, their receptors, and the phe ...201627012870
molecular characterization of a c-type lysozyme from the desert locust, schistocerca gregaria (orthoptera: acrididae).lysozymes are bacteriolytic peptides that are implicated in the insect nonspecific innate immune responses. in this study, a full-length cdna encoding a c-type lysozyme from schistocerca gregaria (sglys) has been cloned and characterized from the fat body of immune-challenged 5(th) instar. the deduced mature lysozyme is 119 amino acid residues in length, has a calculated molecular mass of 13.4 kda and an isoelectric point (ip) of 9.2. sglys showed high identities with other insect lysozymes, ran ...201626997372
microsatellite evolutionary rate and pattern in schistocerca gregaria inferred from direct observation of germline mutations.unravelling variation among taxonomic orders regarding the rate of evolution in microsatellites is crucial for evolutionary biology and population genetics research. the mean mutation rate of microsatellites tends to be lower in arthropods than in vertebrates, but data are scarce and mostly concern accumulation of mutations in model species. based on parent-offspring segregations and a hierarchical bayesian model, the mean rate of mutation in the orthopteran insect schistocerca gregaria was esti ...201526562076
pioneer neurons of the antennal nervous system project to protocerebral pioneers in the grasshopper schistocerca gregaria.the twin nerve tracts of the antenna of the grasshopper schistocerca gregaria are established early in embryogenesis by sibling pairs of pioneers which delaminate from the epithelium into the lumen at the antennal tip. these cells can be uniquely identified via their co-expression of the neuronal labels horseradish peroxidase and the lipocalin lazarillo. the apical pioneers direct axons toward the antennal base where they encounter guidepost-like cells called base pioneers which transiently expr ...201526553379
assaying visual memory in the desert locust.the involvement of associative learning cues has been demonstrated in several stages of feeding and food selection. short neuropeptide f (snpf), an insect neuropeptide whose effects on feeding behavior have previously been well established, may be one of the factors bridging feeding and learning behavior. recently, it was shown in drosophila melanogaster that the targeted reduction of drome-snpf transcript levels significantly reduced sugar-rewarded olfactory memory. while drosophila mainly reli ...201526463192
isolation and characterization of chitosan from different local insects in egypt.chitin was extracted from four different local sources: the shrimp (penaeus monodon), the desert locust (schistocerca gregaria), the honey bee (apis mellifera) and the beetles (calosoma rugosa). chitosan was then obtained by deacetylation of chitin and physicochemically characterized using the fourier transform infrared (ftir) and x-ray diffraction. the moisture content, water binding capacity, fats binding capacity, ash content were determined and chitosans morphology was visualized using the s ...201626459168
isolation, characterization, kinetics, and enzymatic and nonenzymatic microbicidal activities of a novel c-type lysozyme from plasma of schistocerca gregaria (orthoptera: acrididae).a protein, designated as sgl, showing a muramidase lytic activity to the cell wall of the gram-positive bacterium micrococcus lysodeikticus was isolated for the first time from plasma of escherichia coli-immunized fifth instar schistocerca gregaria. the isolated sgl was detected as a single protein band, on both native- and sds-page, has a molecular weight of ∼15.7 kda and an isoelectric point (pi) of ca 9.3 and its antiserum has specifically recognized its isolated form. fifty-nine percentage o ...201525972507
molecular cloning and characterization of the allatotropin precursor and receptor in the desert locust, schistocerca gregaria.allatotropins (ats) are pleiotropic neuropeptides initially isolated from the tobacco hornworm, manduca sexta. in 2008, the first receptor for at-like peptides (atr) was characterized in bombyx mori. since then, atrs have also been characterized in m. sexta, tribolium castaneum, aedes aegypti and bombus terrestris. these receptors show sequence similarity to vertebrate orexin (orx) receptors. when generating an est-database of the desert locust (schistocerca gregaria) central nervous system, we ...201525814925
epigenetics and locust life phase transitions.insects are one of the most successful classes on earth, reflected in an enormous species richness and diversity. arguably, this success is partly due to the high degree to which polyphenism, where one genotype gives rise to more than one phenotype, is exploited by many of its species. in social insects, for instance, larval diet influences the development into distinct castes; and locust polyphenism has tricked researchers for years into believing that the drastically different solitarious and ...201525568455
axogenesis in the antennal nervous system of the grasshopper schistocerca gregaria revisited: the base pioneers.the antennal nervous system of the grasshopper schistocerca gregaria comprises two parallel pathways projecting to the brain, each pioneered early in embryogenesis by a pair of sibling cells located at the antennal tip. en route, the growth cones of pioneers from one pathway have been shown to contact a guidepost-like cell called the base pioneer. its role in axon guidance remains unclear as do the cellular guidance cues regulating axogenesis in the other pathway supposedly without a base pionee ...201525527188
susceptibility to experimental infection of the invertebrate locusts (schistocerca gregaria) with the apicomplexan parasite neospora caninum.neuropathogenesis is a feature of neospora caninum infection. in order to explore this in the absence of acquired host immunity to the parasite, we have tested infection in locusts (schistocerca gregaria). we show for the first time that locusts are permissive to intra-hemocoel infection with n. caninum tachyzoites. this was characterized by alteration in body weight, fecal output, hemoparasitemia, and sickness-related behavior. infected locusts exhibited progressive signs of sickness leading to ...201425493211
above- and belowground herbivory jointly impact defense and seed dispersal traits in taraxacum officinale.plants are able to cope with herbivores by inducing defensive traits or growth responses that allow them to reduce or avoid the impact of herbivores. since above- and belowground herbivores differ substantially in life-history traits, for example feeding types, and their spatial distribution, it is likely that they induce different responses in plants. moreover, strong interactive effects on defense and plant growth are expected when above- and belowground herbivores are jointly present. the str ...201425473483
lipophorins can adhere to dsrna, bacteria and fungi present in the hemolymph of the desert locust: a role as general scavenger for pathogens in the open body cavity.desert locusts are characterized by a highly sensitive and effective rna interference (rnai) response. moreover, delivery of dsrna into the open body cavity will elicit potent silencing effects throughout the body. on the other hand, many other insect species, such as bombyx mori and drosophila melanogaster, lack the ability to efficiently spread the rnai-signal. in this study, we demonstrated that, in the serum of the desert locust, lipophorins adhere to dsrna-fragments. lipophorins can be subd ...201424607637
scavenger receptor-mediated endocytosis facilitates rna interference in the desert locust, schistocerca gregaria.rna interference (rnai) has become a widely used loss-of-function tool in eukaryotes; however, the delivery of double-stranded (ds)rna) to the target cells remains a major challenge when exploiting the rnai-technology. in insects, the efficiency of rnai is highly species-dependent. yet, the mechanism of cell entry in insects has only been characterized in a cell line of the fruit fly, drosophila melanogaster, a species that is well known to be poorly amenable to environmental rnai. in the presen ...201424528536
variant ionotropic receptors are expressed in olfactory sensory neurons of coeloconic sensilla on the antenna of the desert locust (schistocerca gregaria).the behaviour of the desert locust, schistocera gregaria, is largely directed by volatile olfactory cues. the relevant odorants are detected by specialized antennal sensory neurons which project their sensory dendrites into hair-like structures, the sensilla. generally, the responsiveness of the antennal chemosensory cells is determined by specific receptors which may be either odorant receptors (ors) or variant ionotropic receptors (irs). previously, we demonstrated that in locust the co-recept ...201324391446
selectively fluorinated analogs reveal differential olfactory reception and inactivation of green leaf volatiles in insects.the role of the alkyl terminus of green leaf volatile (glv) molecules in olfactory reception and inactivation was examined in three diverse insect species: the beet armyworm,spodoptera exigua (lepidoptera); the colorado potato beetle,leptinotarsa decemlineata (coleoptera); and the desert locust,schistocerca gregaria (orthoptera), using selectively fluorinated analogs of glvs and electroantennograms (eags). when only the magnitude of the depolarization of the eag is considered (a measure of recep ...199324249373
identification of the short neuropeptide f precursor in the desert locust: evidence for an inhibitory role of snpf in the control of feeding.peptides of the short neuropeptide f (snpf) family have been shown to modulate feeding behavior in a wide variety of insect species. while these peptides stimulate feeding and food-searching behavior in drosophila melanogaster and apis mellifera, an opposite effect has recently been demonstrated in the desert locust, schistocerca gregaria. in this study, we elaborate on these observations with the identification of the nucleotide sequence encoding the schgr-snpf precursor and the study of its ro ...201424128610
dye coupling and immunostaining of astrocyte-like glia following intracellular injection of fluorochromes in brain slices of the grasshopper, schistocerca gregaria.injection of fluorochromes such as alexa fluor(®) 568 into single cells in brain slices reveals a network of dye-coupled cells to be associated with the central complex. subsequent immunolabeling shows these cells to be repo positive/glutamine synthetase positive/horseradish peroxidase negative, thus identifying them as astrocyte-like glia. dye coupling fails in the presence of n-heptanol indicating that dye spreads from cell to cell via gap junctions. a cellular network of dye-coupled, astrocyt ...201424048929
production of the biopesticide azadirachtin by hairy root cultivation of azadirachta indica in liquid-phase bioreactors.batch cultivation of azadirachta indica hairy roots was carried out in different liquid-phase bioreactor configurations (stirred-tank, bubble column, bubble column with polypropylene basket, and polyurethane foam disc as root supports) to investigate possible scale-up of the a. indica hairy root culture for in vitro production of the biopesticide azadirachtin. the hairy roots failed to grow in the conventional bioreactor designs (stirred tank and bubble column). however, modified bubble column r ...201323955295
identification of distinct tyraminergic and octopaminergic neurons innervating the central complex of the desert locust, schistocerca gregaria.the central complex is a group of modular neuropils in the insect brain with a key role in visual memory, spatial orientation, and motor control. in desert locusts the neurochemical organization of the central complex has been investigated in detail, including the distribution of dopamine-, serotonin-, and histamine-immunoreactive neurons. in the present study we identified neurons immunoreactive with antisera against octopamine, tyramine, and the enzymes required for their synthesis, tyrosine d ...023595814
in vivo effect of neuropeptide f on ecdysteroidogenesis in adult female desert locusts (schistocerca gregaria).neuropeptides are important regulatory factors that mediate key life processes, both in vertebrates and invertebrates. many insect neuropeptides display pleiotropic activities, which means that they can influence multiple aspects of insect physiology. in the fruit fly, drosophila melanogaster, neuropeptide f (npf) mediates diverse physiological processes, such as learning, stress responses, feeding and male courtship behavior. in locusts, only a truncated form of the predicted "full-length" npf, ...201323524065
the mode of action of juvenile hormone and ecdysone: towards an epi-endocrinological paradigm?in some insect species, two sites of juvenile hormone (jh) synthesis have been reported: the very well documented corpora allata that secrete jh for "general use", and the reproductive system, in particular the male accessory glands, in which the function of the sometimes huge amounts of jh (e.g. in hyalophora cecropia) remains to be clarified. a recent finding in schistocerca gregaria, namely that suppression of the ecdysteroid peak preceding a molt by rnai of the halloween genes spook, phantom ...201323454668
functional characterization of the short neuropeptide f receptor in the desert locust, schistocerca gregaria.whereas short neuropeptide f (snpf) has already been reported to stimulate feeding behaviour in a variety of insect species, the opposite effect was observed in the desert locust. in the present study, we cloned a g protein-coupled receptor (gpcr) cdna from the desert locust, schistocerca gregaria. cell-based functional analysis of this receptor indicated that it is activated by both known isoforms of schgr-snpf in a concentration dependent manner, with ec(50) values in the nanomolar range. this ...201323308260
neuropeptide f regulates male reproductive processes in the desert locust, schistocerca gregaria.although neuropeptide f (npf) has been identified in different insect species, its function has mainly been studied in the fruit fly, drosophila melanogaster, where it regulates diverse physiological processes, such as learning, stress responses and male courtship behavior. in locusts, only a truncated form of the "full-length" npf (the biologically active "trnpf") has been isolated. this 9 aa peptide stimulates oocyte maturation, food intake and weight increase in adult desert locusts (schistoc ...201323295785
regulation of feeding by neuropeptide f in the desert locust, schistocerca gregaria.our knowledge on the physiological function of the insect neuropeptide f (npf) mostly comes from studies in the fruit fly, drosophila melanogaster, where npf was shown to regulate diverse processes, such as feeding, learning and responding to stress. in the desert locust, schistocerca gregaria, only a truncated form of the "full-length" npf (the biologically active "trnpf") has been isolated. in this study, we investigated whether this peptide is involved in the regulation of feeding in this ort ...201323103541
resilin-like protein in the clamp sclerites of the gill monogenean diplozoon paradoxum nordmann, 1832.resilin is a soft and elastic protein, which is found in many exoskeletal structures of arthropods. proteins with similar chemical properties have been described for other invertebrates including monogenean fish parasites. however, for the latter taxon no clear microscopic evidence for a resilin-like protein has been shown so far. here, we present the results of detailed microscopic analyses of the clamp sclerites (attachment devices) of the monogenean diplozoon paradoxum. toluidine blue, which ...201322939032
rnai-mediated knockdown of shade negatively affects ecdysone-20-hydroxylation in the desert locust, schistocerca gregaria.a major breakthrough in elucidating the ecdysteroid biosynthetic pathway in insects was realized with the molecular identification and further functional characterization of the 'halloween' genes. these genes were found to encode cytochrome p450 enzymes catalysing the final steps of ecdysteroid biosynthesis in the dipteran, drosophila melanogaster, and in the lepidoptera, manduca sexta and bombyx mori. a recent report focused on the identification of halloween orthologs in the desert locust, sch ...201222465741
spectral clustering in peptidomics studies allows homology searching and modification profiling: homclus, a versatile tool.many genomes of nonmodel organisms are yet to be annotated. peptidomics research on those organisms therefore cannot adopt the commonly used database-driven identification strategy, leaving the more difficult de novo sequencing approach as the only alternative. the reported tool uses the growing resources of publicly or in-house available fragmentation spectra and sequences of (model) organisms to elucidate the identity of peptides of experimental spectra of nonannotated species. clustering algo ...201222409323
the olfactory co-receptor orco from the migratory locust (locusta migratoria) and the desert locust (schistocerca gregaria): identification and expression pattern.in locusts, olfaction plays a crucial role for initiating and controlling behaviours, including food seeking and aggregation with conspecifics, which underlie the agricultural pest capacity of the animals. in this context, the molecular basis of olfaction in these insects is of particular interest. here, we have identified genes of two orthopteran species, locusta migratoria and schistocera gregaria, which encode the olfactory receptor co-receptor (orco). it was found that the sequences of lmigo ...201122211114
fruitless rnai knockdown in the desert locust, schistocerca gregaria, influences male fertility.in drosophila melanogaster, the male-specific splice isoform of the fruitless gene (fru(m)) encodes a set of transcription factors that are involved in the regulation of male courtship and copulation. recent insights from non-drosophilid insects suggest a conserved evolutionary role for the transcription factor fruitless. in the desert locust, schistocerca gregaria and the german cockroach, blatella germanica, both orthopteran insects, a conserved functional role for fruitless has been proposed. ...201222138053
ammonia transport by terrestrial and aquatic insects.ammonia, an end product from amino acid and nucleic acid metabolism, is highly toxic for most animals. this review will provide an update on nitrogen metabolism in terrestrial and aquatic insects with emphasis on ammonia generation and transport. aspects that will be discussed include metabolic pathways of nitrogenous compounds, the origin of ammonia and other nitrogenous waste products, ammonia toxicity, putative ammonia transporters as well as ammonia transport processes known in insects. ammo ...201122100291
venom lethality and diet: differential responses of natural prey and model organisms to the venom of the saw-scaled vipers (echis).the composition of snake venoms shows a high degree of variation at all taxonomic levels, and natural selection for diet has been implicated as a potential cause. saw-scaled vipers (echis) provide a good model for studying this phenomenon. the venoms of arthropod feeding species of echis are significantly more toxic to natural scorpion prey than those of species which feed predominantly upon vertebrate prey. although testing venom activity on natural prey is important for our understanding of th ...201222079297
Interactive effects of plant-available soil silicon and herbivory on competition between two grass species.The herbivore defence system of true grasses (Poaceae) is predominantly based on silicon that is taken up from the soil and deposited in the leaves in the form of abrasive phytoliths. Silicon uptake mechanisms can be both passive and active, with the latter suggesting that there is an energetic cost to silicon uptake. This study assessed the effects of plant-available soil silicon and herbivory on the competitive interactions between the grasses Poa annua, a species that has previously been repo ...201121868406
grasshopper oral secretions increase salicylic acid and abscisic acid levels in wounded leaves of arabidopsis thaliana.recent investigations showed that the model plant arabidopsis thaliana specifically responds to herbivory-associated molecular patterns by activating a sophisticated signaling network. the lipase activity of insect oral secretions was shown to elevate oxylipin levels when applied to puncture wounds in leaves. the results also demonstrated that the oral secretions of the generalist schistocerca gregaria contained other, probably non-proteinous, elicitors of plant defense responses which induced m ...201121847018
the clock input to the first optic neuropil of drosophila melanogaster expressing neuronal circadian plasticity.in the first optic neuropil (lamina) of the fly's visual system, two interneurons, l1 and l2 monopolar cells, and epithelial glial cells show circadian rhythms in morphological plasticity. these rhythms depend on clock gene period (per) and cryptochrome (cry) expression. in the present study, we found that rhythms in the lamina of drosophila melanogaster may be regulated by circadian clock neurons in the brain since the lamina is invaded by one neurite extending from ventral lateral neurons; the ...201121760878
spatial heterogeneity in resource distribution promotes facultative sociality in two trans-saharan migratory birds.migrant populations must cope not only with environmental changes in different biomes, but also with the continuous constraints imposed by human-induced changes through landscape transformation and resource patchiness. theoretical studies suggest that changes in food distribution can promote changes in the social arrangement of individuals without apparent adaptive value. empirical research on this subject has only been performed at reduced geographical scales and/or for single species. however, ...201121731640
The inhibitory effect of the fungal toxin, destruxin A, on behavioural fever in the desert locust.During an infection locusts behaviourally fever by seeking out higher environmental temperatures. This behaviour places the pathogen at sub-optimal growth temperatures while improving the efficiency of the immune system, thereby prolonging the lifespan of the host. It is therefore in the interest of the pathogen to either adapt to fever-like temperatures or to evolve mechanisms to interfere with, or inhibit fever. We investigated the behavioural fever response of desert locusts to two fungal pat ...201121729702
role of the halloween genes, spook and phantom in ecdysteroidogenesis in the desert locust, schistocerca gregaria.the functional characterization of the halloween genes represented a major breakthrough in the elucidation of the ecdysteroid biosynthetic pathway. these genes encode cytochrome p450 enzymes catalyzing the final steps of ecdysteroid biosynthesis in the dipteran drosophila melanogaster and the lepidoptera manduca sexta and bombyx mori. this is the first report on the identification of two halloween genes, spook (spo) and phantom (phm), from a hemimetabolous orthopteran insect, the desert locust s ...201121708158
astrocyte-like glia associated with the embryonic development of the central complex in the grasshopper schistocerca gregaria.in this study we employed the expression of the astrocyte-specific enzyme glutamine synthetase, in addition to the glia-specific marker repo, to characterize glia cell types associated with the embryonic development of the central complex in the grasshopper schistocerca gregaria. double labeling experiments reveal that all glutamine synthetase-positive cells associated with the central complex are also repo-positive and horseradish peroxidase-negative, confirming they are glia. early in embryoge ...201121556852
lipase activity in insect oral secretions mediates defense responses in arabidopsis thaliana.how plants perceive herbivory is not yet well understood. we investigated early responses of the model plant arabidopsis thaliana to attack from the generalist grasshopper herbivore, schistocerca gregaria (caelifera). when compared to wounding alone, schistocerca gregaria attack and the application of grasshopper oral secretions (gs) to puncture wounds elicited a rapid accumulation of various oxylipins, including 13-hydroperoxy octadecatrienoic acid, 12-oxo-phytodienoic acid (opda), jasmonic aci ...201121546453
high-affinity small protein inhibitors of human chymotrypsin c (ctrc) selected by phage display reveal unusual preference for p4' acidic residues.human chymotrypsin c (ctrc) is a pancreatic protease that participates in the regulation of intestinal digestive enzyme activity. other chymotrypsins and elastases are inactive on the regulatory sites cleaved by ctrc, suggesting that ctrc recognizes unique sequence patterns. to characterize the molecular determinants underlying ctrc specificity, we selected high-affinity substrate-like small protein inhibitors against ctrc from a phage library displaying variants of a natural chymotrypsin inhibi ...201121515688
transcriptome analysis of the desert locust central nervous system: production and annotation of a schistocerca gregaria est database.the desert locust (schistocerca gregaria) displays a fascinating type of phenotypic plasticity, designated as 'phase polyphenism'. depending on environmental conditions, one genome can be translated into two highly divergent phenotypes, termed the solitarious and gregarious (swarming) phase. although many of the underlying molecular events remain elusive, the central nervous system (cns) is expected to play a crucial role in the phase transition process. locusts have also proven to be interestin ...201121445293
fruitless rnai knockdown in males interferes with copulation success in schistocerca gregaria.in drosophila melanogaster, the male-specific splice isoform of the fruitless gene (fru(m)) codes for a set of transcription factors that are involved in the regulation of male courtship and copulation. fru(m) is expressed in an interconnected neuronal circuit containing central and sensory neurons as well as motor neurons. a partial sequence from the schistocerca gregaria fru-gene from an est database allowed quantitative real time analysis of fru-expression in adult locusts, and revealed the h ...201121296153
an fmrfamide antiserum differentiates between populations of antigens in the brain and retrocerebral complex of the locust, schistocerca gregaria.the distribution of fmrfamide-irmunoreactive cell bodies in the brain and retrocerebral complex of the locust, schistocerca gregaria, is described. most of the immunoreactive cell bodies are found in the pars intercerebralis and in the optic lobes. many, but not all, of the cell bodies also react with an antiserum raised against bovine pancreatic polypeptide, but this antiserum also reveals another population of cells that stain selectively with this antiserum. in addition to the cell bodies, nu ...198721253765
proliferative cell types in embryonic lineages of the central complex of the grasshopper schistocerca gregaria.the central complex of the grasshopper schistocerca gregaria develops to completion during embryogenesis. a major cellular contribution to the central complex is from the w, x, y, z lineages of the pars intercerebralis, each of which comprises over 100 cells, making them by far the largest in the embryonic protocerebrum. our focus has been to find a cellular mechanism that allows such a large number of cell progeny to be generated within a restricted period of time. immunohistochemical visualiza ...201020571828
behavior of geladas and other endemic wildlife during a desert locust outbreak at guassa, ethiopia: ecological and conservation implications.desert locust (schistocerca gregaria) outbreaks have occurred repeatedly throughout recorded history in the horn of africa region, devastating crops and contributing to famines. in june 2009, a desert locust swarm invaded the guassa plateau, ethiopia, a large and unusually intact afroalpine tall-grass ecosystem, home to important populations of geladas (theropithecus gelada), ethiopian wolves (canis simensis), thick-billed ravens (corvus crassirostris), and other ethiopian or horn of africa ende ...201020333438
sexual differentiation in adult insects: male-specific cuticular yellowing in schistocerca gregaria as a model for reevaluating some current (neuro)endocrine concepts.changes in the color of the cuticle, days after the completion of hardening, are rare in adult insects. even more so when such changes are specific to one sexual form and coincide with sexual maturation. adult males of the desert locust schistocerca gregaria deposit a well characterized 'yellow protein' in their cuticle about 10 days after the adult molt, but only if they live under crowded (gregarious) conditions. isolated-reared (solitarious) males do not turn yellow, neither do the females. u ...201020223244
crowded locusts produce hatchlings vulnerable to fungal attack.transgenerational effects of parental experience on offspring immunity are well documented in the vertebrate literature (where antibodies play an obligatory role), but have only recently been described in invertebrates. we have assessed the impact of parental rearing density upon offspring disease resistance by challenging day-old locust hatchlings (schistocerca gregaria) from either crowd- or solitary-reared parents with the fungal pathogen metarhizium anisopliae var. acridum. when immersed in ...200919675004
identification and validation of housekeeping genes in brains of the desert locust schistocerca gregaria under different developmental conditions.to obtain reliable quantitative rt-pcr data, normalization relative to stable housekeeping genes is required. however, in practice, expression levels of 'typical' housekeeping genes have been found to vary between tissues and under different experimental conditions. to date, validation studies of reference genes in insects are extremely rare and have never been performed in locusts. in this study, putative housekeeping genes were identified in the desert locust, schistocerca gregaria and two dif ...200919508726
quantitative determination of catecholic degradation products from insect sclerotized cuticles.acid hydrolysates of cuticle from various insect species were quantitatively analyzed for five catecholic amino acid adducts. four of the adducts are ketocatechols; in three of them the amino acid moiety, either lysine, glycine or beta-alanine, is connected via its amino group to the alpha-carbon atom of 3,4-dihydroxyacetophenone, in the fourth a tyrosine residue is connected to the same position via its phenolic group. the fifth adduct contains histidine linked via its imidazole-ring to the bet ...200818675913
fine structure of the rectal pads in the desert locust schistocerca gregaria with reference to the mechanism of water uptake.the rectal pads of schistocerca gregaria are composed of three different cell types: epithelial, secondary and junctional cells. the rectal pads are interconnected by simple rectal cells and both are lined internally by a articular intima. the epithelial cells exhibit extensive infoldings of the apical plasma membranes that are closely associated with mitochondria. their lateral plasma membranes are highly folded around large mitochondria and enclose intercellular channels and spaces. they are u ...199218621204
embryonic development of a peripheral nervous system: nerve tract associated cells and pioneer neurons in the antenna of the grasshopper schistocerca gregaria.the grasshopper antenna is an articulated appendage associated with the deutocerebral segment of the head. in the early embryo, the meristal annuli of the antenna represent segment borders and are also the site of differentiation of pioneer cells which found the dorsal and ventral peripheral nerve tracts to the brain. we report here on another set of cells which appear earlier than the pioneers during development and are later found arrayed along these tracts at the border of epithelium and lume ...200718089112
embryonic development of the sensory innervation of the antenna of the grasshopper schistocerca gregaria.the establishment of the sensory nervous system of the antenna of the grasshopper schistocerca gregaria was examined using immunocytochemical methods and in the light of the appendicular and articulated nature of this structure. the former is demonstrated first by the expression pattern of the segment polarity gene engrailed in the head neuromere innervating the antenna, the deutocerebrum. engrailed expression is present in identified deutocerebral neuroblasts and, as elsewhere in the body, is c ...200418089045
interaction between paranosema locustae and metarhizium anisopliae var. acridum, two pathogens of the desert locust, schistocerca gregaria under laboratory conditions.the interaction between two pathogens, the microsporidian paranosema locustae canning and the fungus metarhizium anisopliae var. acridum driver and milner was studied under laboratory conditions in an attempt to develop an improved method of microbial control for the desert locust, schistocerca gregaria forskål. fifth-instar locust nymphs, reared in the laboratory, were treated with various concentrations of one of the two pathogens or with both pathogens. the numbers of locusts killed were reco ...200818005982
sensitivity and speed of induced defense of cabbage (brassica oleracea l.): dynamics of bolox expression patterns during insect and pathogen attack.the lipoxygenase pathway is involved in the early steps of plant responses to herbivorous insects and phytopathogens. induced defenses in the crucifer brassica oleracea have been well documented. here, we have cloned a lipoxygenase (lox) from b. oleracea (bolox). the sequence reveals that the bolox protein has a transit peptide for chloroplast targeting, which is characteristic for class 2 loxs involved in jasmonic acid (ja) biosynthesis which takes place in the chloroplast. phylogenetic analysi ...200717977145
spectral properties of identified polarized-light sensitive interneurons in the brain of the desert locust schistocerca gregaria.many migrating animals employ a celestial compass mechanism for spatial navigation. behavioral experiments in bees and ants have shown that sun compass navigation may rely on the spectral gradient in the sky as well as on the pattern of sky polarization. while polarized-light sensitive interneurons (pol neurons) have been identified in the brain of several insect species, there are at present no data on the neural basis of coding the spectral gradient of the sky. in the present study we have ana ...200717401118
application of toxins from the entomopathogenic bacterium, xenorhabdus nematophila, for the control of insects on foliage.larvae of the beet armyworm, spodoptera exigua, and the diamondback moth, plutella xylostella, and nymphs of the desert locust, schistocerca gregaria were controlled by the application of either cell suspensions from the bacterium, xenorhabdus nematophila or filtrates containing cell-free toxins. since there was no significant differences between the two treatments it was concluded that toxins produced by the bacterium were responsible for the lethal effects obtained. cells of xenorhabdus nemato ...200617390798
the contribution of surface waxes to pre-penetration growth of an entomopathogenic fungus on host cuticle.a locust wing bioassay, that allowed an entomopathogenic fungus to be removed from host cuticle before penetration, was used to investigate the role of surface lipids and waxes in pre-penetration growth of the specific locust pathogen metarhizium anisopliae var. acridum. sem and atomic force electron microscopy showed the impact of the fungus on the architecture of the cuticle surface. although the fungus can germinate on authentic alkanes as the sole carbon source, only low levels of germinatio ...200717324760
aspects of cuticular sclerotization in the locust, scistocerca gregaria, and the beetle, tenebrio molitor.the number of reactive amino groups in cuticular proteins decreases during the early period of insect cuticular sclerotization, presumably due to reaction with oxidation products of n-acetyldopamine (nada) and n-beta-alanyldopamine (nbad). we have quantitated the decrease in cuticular n-terminal amino groups and lysine epsilon-amino groups during the first 24h of sclerotization in adult locusts, schistocerca gregaria, and in larval and adult beetles, tenebrio molitor, as well as the increase in ...200717296497
insect satiety: sulfakinin localization and the effect of drosulfakinin on protein and carbohydrate ingestion in the blow fly, phormia regina (diptera: calliphoridae).sulfakinins, which are satiety factors in invertebrates, have previously been shown to inhibit feeding in the german cockroach and desert locust. this study examines the occurrence of sulfakinin immunoreactivity and the role of sulfakinin as a feeding satiety factor in the black blow fly, phormia regina. specifically, this study examines the effect of sulfakinin on two of the blow fly's nutrient requirements (i.e., carbohydrates and proteins). we observed sulfakinin immunoreactive cells in the b ...200717166511
both prothoracicotropic hormone and an autocrine factor are involved in control of prothoracic gland ecdysteroidogenesis in locusta migratoria and schistocerca gregaria.in bombyx mori, ecdysteroidogenesis by the prothoracic glands (pgs) is controlled by both prothoracicotropic hormone (ptth) and a factor secreted by the glands themselves. this factor, which is active both in vitro and in vivo, has been named 'autocrine factor' (af). to find out whether or not this dual control also exists in other species, in particular in hemimetabolous ones, we applied similar methods as were used to discover af in bombyx to the locusts locusta migratoria and schistocerca gre ...200717157412
a novel locust (schistocerca gregaria) serine protease inhibitor with a high affinity for neutrophil elastase.we have purified to homogeneity two forms of a new serine protease inhibitor specific for elastase/chymotrypsin from the ovary gland of the desert locust schistocerca gregaria. this protein, greglin, has 83 amino acid residues and bears putative phosphorylation sites. amino acid sequence alignments revealed no homology with pacifastin insect inhibitors and only a distant relationship with kazal-type inhibitors. this was confirmed by computer-based structural studies. the most closely related hom ...200616839309
the evolution of hexapod engrailed-family genes: evidence for conservation and concerted evolution.phylogenetic analyses imply that multiple engrailed-family gene duplications occurred during hexapod evolution, a view supported by previous reports of only a single engrailed-family gene in members of the grasshopper genus schistocerca and in the beetle tribolium castaneum. here, we report the cloning of a second engrailed-family gene from schistocerca gregaria and present evidence for two engrailed-family genes from four additional hexapod species. we also report the existence of a second engr ...016790405
resource distribution mediates synchronization of physiological rhythms in locust groups.synchronized behaviour is common in animal groups. in ant colonies, synchronization occurs because active ants stimulate their neighbours to activity. we use oscillator theory to explain how stimulation from active neighbours synchronizes activity in groups of solitarious locusts via entrainment of internal physiological rhythms. we also show that the spatial distribution of food resources controls coupling between individual locusts and the emergence of synchronized activity. in locusts (schist ...200616777746
phylogenetic and structural relationships of the pr5 gene family reveal an ancient multigene family conserved in plants and select animal taxa.pathogenesis-related group 5 (pr5) plant proteins include thaumatin, osmotin, and related proteins, many of which have antimicrobial activity. the recent discovery of pr5-like (pr5-l) sequences in nematodes and insects raises questions about their evolutionary relationships. using complete plant genome data and discovery of multiple insect pr5-l sequences, phylogenetic comparisons among plants and animals were performed. all pr5/pr5-l protein sequences were mined from genome data of a member of ...200616736102
silica in grasses as a defence against insect herbivores: contrasting effects on folivores and a phloem feeder.1. silica, deposited as opaline phytoliths in the leaves of grasses, constitutes 2-5% of dry leaf mass, yet its function remains unclear. it has been proposed that silica may act as an antiherbivore defence by increasing the abrasiveness and reducing the digestibility of grass leaves, although there is little direct experimental evidence to support this. 2. we investigated the effects of manipulated silica levels on the abrasiveness of the leaves of five grass species. we also examined the effec ...200616638012
local binding with globally distributed changes in a small protease inhibitor upon enzyme binding.complexation of the small serine protease inhibitor schistocerca gregaria chymotrypsin inhibitor (sgci), a member of the pacifastin inhibitor family, with bovine chymotrypsin was followed by nmr spectroscopy. (1)h-(15)n correlation (hsqc) spectra of the inhibitor with increasing amounts of the enzyme reveal tight and specific binding in agreement with biochemical data. unexpectedly, and unparalleled among canonical serine protease inhibitors, not only residues in the protease-binding loop of the ...200616623717
purification, characterisation and titre of the haemolymph juvenile hormone binding proteins from schistocerca gregaria and gryllus bimaculatus.juvenile hormone binding proteins (jhbps) were extracted from the haemolymph of adult desert locusts, schistocerca gregaria, and mediterranean field crickets, gryllus bimaculatus. the jhbps were purified by polyethyleneglycol precipitation, filtration through molecular weight cut off filters and chromatography on a hitrap heparin column. the juvenile hormone (jh) binding activity of the extracts was measured using a hydroxyapatite assay and the purification progress was monitored by native gel c ...200616384579
sgbeta1, a novel locust (schistocerca gregaria) non-alpha nicotinic acetylcholine receptor-like subunit with homology to the drosophila melanogaster dbeta1 subunit.the cloning, sequencing and functional expression of sgbeta1, a novel locust (schistocerca gregaria) non-alpha nicotinic acetylcholine receptor (nachr) subunit is described. this subunit shows 80% identity with the drosophila melanogaster dbeta1 and 92% identity with the locusta migratoria beta1, non-alpha subunits but only 38% identity to sgalpha1 (also referred to as alphal1), a previously cloned s. gregaria nachr alpha-subunit. when expressed in xenopus laevis oocytes, sgbeta1 does not respon ...200516177887
novel insect orcokinins: characterization and neuronal distribution in the brains of selected dicondylian insects.orcokinins are a family of myotropic neuropeptides identified in various decapod crustaceans and recently in a cockroach. their presence in the crustacean nervous system and hemolymph suggests that they act as hormones and as locally acting neuromodulators. to provide further evidence for the existence of orcokinins in insects, we identified a novel orcokinin-related peptide in the locust schistocerca gregaria and used an antiserum against asn13-orcokinin for immunostaining in the brains of sele ...200516041719
ace inhibitory activity in enzymatic hydrolysates of insect protein.in this paper, ace inhibitory activity in insect protein hydrolyzed by various enzymes (gastrointestinal proteases, alcalase, and thermolysin) is reported for the first time. four insects of different insect orders were tested: spodoptera littoralis (lepidoptera), bombyx mori (lepidoptera), schistocerca gregaria (orthoptera), and bombus terrestris (hymenoptera). ace inhibitory activity was measured by two different methods: a spectrophotometric method using fapgg (2-furanacryloyl-phenylalanyl-gl ...200515969498
extended intermolecular interactions in a serine protease-canonical inhibitor complex account for strong and highly specific inhibition.we have previously shown that a trypsin inhibitor from desert locust schistocerca gregaria (sgti) is a taxon-specific inhibitor that inhibits arthropod trypsins, such as crayfish trypsin, five orders of magnitude more effectively than mammalian trypsins. thermal denaturation experiments, presented here, confirm the inhibition kinetics studies; upon addition of sgti the melting temperatures of crayfish and bovine trypsins increased 27 degrees c and 4.5 degrees c, respectively. to explore the stru ...200515922357
developmental and transcriptional responses to host and nonhost cuticles by the specific locust pathogen metarhizium anisopliae var. acridum.transcript patterns elicited in response to hosts can reveal how fungi recognize suitable hosts and the mechanisms involved in pathogenicity. these patterns could be fashioned by recognition of host-specific topographical features or by chemical components displayed or released by the host. we investigated this in the specific locust pathogen metarhizium anisopliae var. acridum. only host (schistocerca gregaria) cuticle stimulated the full developmental program of germination and differentiation ...200515879528
colorado potato beetle larvae on potato plants expressing a locust proteinase inhibitor.the natural defence system of plants often involves inhibitors of digestive enzymes of their pests. modem and environmental-friendly methods try to increase this plant resistance by expressing heterologous protease inhibitors in crops. here we report the effects of expressing a gene from desert locust (schistocerca gregaria) encoding two serine protease inhibitors in potato on colorado potato beetle (leptinotarsa decemlineata) larvae. the gene encoding both peptides on a single chain was used fo ...200415759425
characterization of two novel pacifastin-like peptide precursor isoforms in the desert locust (schistocerca gregaria): cdna cloning, functional analysis and real-time rt-pcr gene expression studies.in the last decade, a new serine protease inhibitor family has been described in arthropods. eight members of the family were purified from locusts and share a conserved cysteine array (cys-xaa(9-12)-cys-asn-xaa-cys-xaa-cys-xaa(2-3)-gly-xaa(3-6)-cys-thr-xaa3-cys) with nine inhibitory domains of the light chain of the crayfish protease inhibitor, pacifastin (plds; pacifastin light chain domains). using cdna cloning, several pacifastin-related precursors have been identified, encoding additional p ...200515631618
emergency prevention system (empres) for transboundary animal and plant pests and diseases. the empres-livestock: an fao initiative.the food and agriculture organization of the united nations (fao) decided that the organization should be focusing on the goal of enhancing world food security and the fight against transboundary animal diseases and plant pests. a mandate was obtained from the governing council and conference to establish two new special programmes to address these fundamental issues. the first is the special programme on food security and the second is the emergency prevention system against transboundary anima ...200415604466
conservation of capa peptide-induced nitric oxide signalling in diptera.in d. melanogaster malpighian (renal) tubules, the capa peptides stimulate production of nitric oxide (no) and guanosine 3', 5'-cyclic monophosphate (cgmp), resulting in increased fluid transport. the roles of no synthase (nos), no and cgmp in capa peptide signalling were tested in several other insect species of medical relevance within the diptera (aedes aegypti, anopheles stephensi and glossina morsitans) and in one orthopteran out-group, schistocerca gregaria. nos immunoreactivity was detect ...200415498959
chlorinated tyrosine derivatives in insect cuticle.a method for quantitative measurement of 3-monochlorotyrosine and 3,5-dichlorotyrosine in insect cuticles is described, and it is used for determination of their distribution in various cuticular regions in nymphs and adults of the desert locust, schistocerca gregaria. the two chlorinated tyrosine derivatives were present in all analyzed regions in mature adult locusts, the highest concentrations were found in the sclerotized cuticle of femur and tibia, but significant amounts were also present ...200415475302
differential transcription in defined parts of the insect brain: comparative study utilizing drosophila melanogaster and schistocerca gregaria.the brain of all higher organisms has a modular architecture. processing of various tasks, such as learning, olfaction, or motor control is performed in specialized brain areas, characterized by morphological and molecular peculiarities. to identify those genes that are transcribed in only one region of the insect brain, we chose two different approaches, differential display pcr and dna array hybridization, with two different insect species, the desert locust schistocerca gregaria and the fruit ...200415378392
a conserved domain of alkaline phosphatase expression in the malpighian tubules of dipteran insects.malpighian (renal) tubules are key components of the insect osmoregulatory system and show correspondingly great diversity in both number and length. recently, the organisation of the drosophila melanogaster tubule has been elucidated by enhancer trapping, and an array for functional properties has been shown to align with the functional domains. in drosophila, there is a lower tubule domain, which coincides with expression of alkaline phosphatase and delineates the absorptive region of the tubu ...200415326206
comparative role of proteins in transport of hch-isomers in desert locust, schistocerca gregaria forskal and bovines.the studies on binding of hexachlorocyclohexane (hch) with carrier proteins were carried out to establish the role of proteins in the transport of insecticides in insects. sephadex g-200 column chromatography resolved haemolymph of adult male desert locust, schistocerca gregaria into three major protein peaks. there was significant binding of gamma-hch with first protein peak (f1). two classes of binding sites were observed on first protein peak for gamma-hch. however low level of binding was ob ...200315266906
partial characterisation of a trypanosome-lysing factor from the midgut of the desert locust, schistocerca gregaria.screening and biochemical characterisation of trypanosome-lysing factor (trypanolysin) from non-vector insect, schistocerca gregaria.200315248675
comparison of anti-feedant and insecticidal activity of nimbin and salannin photo-oxidation products with neem (azadirachta indica) limonoids.photo-oxidation of the neem limonoids nimbin and salannin with uv light in the presence of oxygen gives two isomeric lactone products per limonoid, nimbinolide and isonimbinolide, and salanninolide and isosalanninolide, respectively. when compared in insect tests with the important limonoids of neem seeds, azadirachtin, nimbin and salannin, isonimbinolide and isosalanninolide show activity greater than that of nimbin or salannin and in some respects show activity approaching that of azadirachtin ...200415154512
desert locust control in ecologically sensitive areas: need for guidelines.chemical control of desert locust (dl) is carried out over large areas of land, covering a range of different landscapes and ecosystems. there are no real restrictions for spraying in or close to environmentally sensitive areas and awareness of sensitivity is not always obvious to the people involved in control. however, concern about environmental issues in connection with dl control is growing and clear guidelines are needed. the objectives were: to identify and delineate areas particularly se ...200314703905
behavioral analysis of polarization vision in tethered flying locusts.for spatial navigation many insects rely on compass information derived from the polarization pattern of the sky. we demonstrate that tethered flying desert locusts (schistocerca gregaria) show e-vector-dependent yaw-torque responses to polarized light presented from above. a slowly rotating polarizer (5.3 degrees s(-1)) induced periodic changes in yaw torque corresponding to the 180 degrees periodicity of the stimulus. control experiments with a rotating diffuser, a weak intensity pattern, and ...200414648100
the effect of manipulating ecdysteroid signaling on embryonic eye development in the locust schistocerca americana.adult body plan differentiation in holometabolous insects depends on global induction and control by ecdysteroid hormones during the final phase of postembryogenesis. studies in drosophila melanogaster and manduca sexta have shown that this pertains also to the development of the compound eye retina. it is unclear whether the hormonal control of postembryonic eye development in holometabolous insects represents evolutionary novelty or heritage from hemimetabolous insects, which develop compound ...200314618403
structure-oriented rational design of chymotrypsin inhibitor models.three peptides modelling a highly potent, 35-residue chymotrypsin inhibitor (schistocerca gregaria chymotrypsin inhibitor) were designed and synthesized by convergent peptide synthesis. for each model peptide, the inhibitory constant (ki) on chymotrypsin and the solution structure were determined. in addition, molecular dynamics calculations were performed for all of them. two models containing approximately half of the parent inhibitor (17 of 35 residues) were designed and subsequently found to ...200314560053
bacterial production and purification of sgpi-1 and sgpi-2, two peptidic serine protease inhibitors from the desert locust, schistocerca gregaria.the last decade, a new serine protease inhibitor family has been described in arthropods. eight members were purified from the locusts locusta migratoria (lmpi-1-2 and hi) and schistocerca gregaria (sgpi-1-5) and 11 additional locust peptides were identified by cdna cloning. furthermore, the light chain of the 155-kda heterodimeric protease inhibitor pacifastin, from the freshwater crayfish pacifastacus leniusculus, was found to be composed of nine consecutive inhibitory domains (plds). these do ...200314550636
study on the occurrence of some microorganisms in locusts, schistocerca gregaria (forsk.) and their toxicological effects on laboratory animals. 196314121845
toxicity and pathogenicity of metarhizium anisopliae var. acridum (deuteromycotina, hyphomycetes) and fipronil to the fringe-toed lizard acanthodactylus dumerili (squamata: lacertidae).reptiles in arid and semiarid zones are frequently exposed to insecticides sprayed to control locusts and grasshoppers. we evaluated the toxicity and pathogenicity of new biological and chemical control agents to the fringe-toed lizard acanthodactylus dumerili in mauritania, west africa. a mycoinsecticide based on spores of the entomopathogenic fungus metarhizium anisopliae var. acridum (isolate imi 330189, green muscle) was tested at high challenge concentrations, using three exposure routes. t ...200312836967
expression of phase-specific haemolymph polypeptides in a laboratory strain and field catches of schistocerca gregaria.uvarov's theory of locust phase polymorphism implies a differential phase-specific gene expression. it was the goal of the present investigation to provide data on the molecular level for this concept. we used the technique of 2d gel electrophoresis to generate haemolymph polypeptide maps from mature locust males. under the given conditions we identified 238 polypeptide spots by their molecular weight and isoelectrical point. isolated and crowded males from the mainz strain, all originating from ...199912770270
parturition hormone in the tsetse glossina morsitans: activity in reproductive tissues from other species and response of tsetse to identified neuropeptides and other neuroactive compounds.parturition hormone (ph) activity is present not only in the uterus of the tsetse glossina morsitans but also in the oviducts of bombyx mori and schistocerca gregaria, as well as the ejaculatory duct of s. gregaria males. activity thus appears to be present in the reproductive ducts of diverse insect taxa. to determine whether any of the common insect neuropeptides are capable of mimicking the effect of ph, 35 identified neuropeptides and analogs were evaluated for ph activity. modest ph activit ...200012770225
the immune response of the desert locust schistocerca gregaria during mycosis of the entomopathogenic fungus, metarhizium anisopliae var acridum.topical application of metarhizium anisopliae var acridum to the desert locust schistocerca gregaria resulted in changes in the biochemistry and antimicrobial defenses of the haemolymph. m. anisopliae var acridum colonized the host haemolymph from day two post application. the haemocytes did not attach to, phagocytose or nodulate elements of the fungus. however, the presence of the fungus appeared to stimulate hemocyte aggregation over the first few days of mycosis though the number of aggregate ...200012770206
proteolytic breakdown of the neb-trypsin modulating oostatic factor (neb-tmof) in the hemolymph of different insects and its gut epithelial transport.the degradation of the unblocked hexapeptide, trypsin modulating oostatic factor of the flesh fly neobellieria (sarcophaga) bullata (neb-tmof) was studied in vitro in the hemolymph of the lepidopteran spodoptera frugiperda, the orthopteran schistocerca gregaria and the dictyopteran leucophaea maderae. the half-life in the different species varied from approximately 3min in l. maderae to approximately 25min in s. gregaria. purification of the degradation products and esi-qq-oa-tof mass spectromet ...200112770174
insect larvae contain substances toxic to adults: the discovery of paralysins.acidic methanolic extracts of larvae of nine different insect species were found to contain substances that cause a lethal effect in the adult stage of the same species and of other species. these endogenous toxic substances, apparently being widely spread over the class of insects, were designated as paralysins, because of their immediate and observable paralytic effect upon injection. the developmental concentration curves of five different species of insects (galleria mellonella (lepidoptera) ...199812770158
eicosanoid involvement in the regulation of behavioral fever in the desert locust, schistocerca gregaria.the desert locust schistocerca gregaria behaviorally thermoregulates in order to try and maintain a favoured "set point" body temperature. locusts infected with the deuteromycete fungal pathogen metarhizium anisopliae var acridumchoose a significantly elevated temperature. this "behavioral fever" greatly delays the progress of mycosis. we have confirmed this phenomenon and shown that desert locusts also fever when infected with the bacterial pathogen serratia marcescens. elevation in the prefere ...200312655606
evidence for oxygen and carbon dioxide receptors in insect cns influencing ventilation.ventilatory efferent discharges in the isolated central nervous system (cns) of the lubber grasshopper taeniopoda eques were recorded and the change of ventilatory rates were measured in correlation to changing concentrations of oxygen and carbon dioxide. these in vitro responses were compared to the ventilatory rates of intact animals exposed to various gas tensions. we found highly significant effects of oxygen on the ventilatory response of both the in vitro cns and the intact animals, with v ...200212443917
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