| methyllycaconitine and (+)-anatoxin-a differentiate between nicotinic receptors in vertebrate and invertebrate nervous systems. | specific high-affinity binding sites for 125i-alpha-bungarotoxin and (-)-[3h]nicotine have been measured in rat brain and locust (schistocerca gregaria) ganglia. the binding sites for 125i-alpha-bungarotoxin had similar kd values of 1.5 x 10(-9) and 0.8 x 10(-9) m for rat and locust preparations, respectively; the corresponding values for the (-)-[3h]nicotine-binding site were 9.3 x 10(-9) and 1.7 x 10(-7) m. methyllycaconitine (mla) potently inhibited 125i-alpha-bungarotoxin binding in both rat ... | 1988 | 3338564 |
| a study of cyclic amp-dependent protein phosphorylation in schistocerca gregaria cns: a comparison to that in mammalian cns. | 1. the effect of cyclic amp (10 microm) on the incorporation of 32p into protein was studied in cell-free preparations of schistocerca gregaria cerebral ganglia. 2. cyclic amp-dependent phosphorylation of total protein was maximal after 60 sec, had a ph optimum of 7 to 8, was not affected by temperature (22-37 degrees c) and had a km of 77 microm atp. 3. cyclic amp increased the phosphorylation of total and specific protein in soluble fractions greater than synaptosomal greater than microsomal g ... | 1988 | 2834140 |
| amino acid receptors from insect muscle: electrophysiological characterization in xenopus oocytes following expression by injection of mrna. | poly(a)+ messenger ribonucleic acid (mrna) was extracted from leg muscles of the locust schistocerca gregaria and injected into oocytes of xenopus laevis. after 5-10 days incubation, receptors for l-glutamate, l-quisqualate, dl-ibotenate and gamma-aminobutyric acid (gaba) were expressed. agonist-induced currents were dose-dependent, and, in the concentration range 1 microm to 1 mm, generally had peak values of 50 na. the responses to all agonists, apart from gaba, exhibited desensitization which ... | 1990 | 2176711 |
| gamma-aminobutyric acid receptor complex of insect cns: characterization of a benzodiazepine binding site. | the specific binding of [n-methyl-3h]flunitrazepam ([3h]fnzp) to a membrane fraction from the supraoesophageal ganglion of the locust (schistocerca gregaria) has been measured. the ligand binds reversibly with a kd of 47 nm. the binding is ca2+-dependent, a property not found for the equivalent binding site in vertebrate brain. the pharmacological characteristics of the locust binding site show similarities to both central and peripheral benzodiazepine receptors in mammals. thus binding is enhan ... | 1986 | 3021910 |
| the relationship of mucoid substances and ion and water transport, with new data on intestinal goblet cells and a model for gastric secretion. | it is known from the physical chemistry that mucoid substances (glycosaminoglycans, proteoglycans, glycoproteins) constitute polyanionic gels with anomalous colligative behaviour and differential preference for binding some cations such as h+, k+, ca2+. the mucus secreting membranes in animals also constitute ion and water transporting epithelia with morphologically characterised pericellular compartments. these pericellular compartments are not free-fluid spaces as is assumed in conventional ph ... | 1989 | 2701492 |
| sequence and functional expression of a single alpha subunit of an insect nicotinic acetylcholine receptor. | we report the isolation and sequence of a cdna clone that encodes a locust (schistocerca gregaria) nervous system nicotinic acetylcholine receptor (achr) subunit (alpha l1). the calculated molecular weight of the unglycosylated polypeptide, which contains in the proposed extracellular domain two adjacent cysteine residues which are characteristic of alpha (ligand binding) subunits, is 60,641 daltons. injection into xenopus oocytes, of rna synthesized from this clone in vitro, results in expressi ... | 1990 | 1702381 |
| purification of choline acetyltransferase from the locust schistocerca gregaria and production of serum antibodies to this enzyme. | choline acetyltransferase (chat; ec 2.3.1.6) was purified from the heads of schistocerca gregaria to a final specific activity of 1.61 mumol acetylcholine (ach) formed min-1 mg-1 protein. the molecular mass of the enzyme as determined by gel filtration is 66,800 daltons. the final enzyme preparation showed one major band at 65,000 daltons on sodium dodecyl sulfate (sds)-polyacrylamide gel electrophoresis, which corresponds with the native molecular mass of the enzyme, a band at 56,000 daltons, a ... | 1988 | 3335852 |
| a study of the protozoa associated with some harmful insects in the local environment. | the present study includes finding resulting from examination of three species of harmful insects, periplaneta americana, schistocerca gregaria and anacanthoterms ochraceus, collected from six cities in the central region of saudi arabia. two species of septate gregarines of the genus gregarina dufor, were found g. blattarum (siebold) from mid gut of p. americana and g. rigida from gut of s. gregaria, also six species of mastigophora in gut of white ant a. ochraceus, trichonympha campanula, spir ... | 1990 | 2332640 |
| partial characterization of specific inducers of a cuticle-degrading protease from the insect pathogenic fungus metarhizium anisopliae. | the insect pathogenic fungus metarhizium anisopliae produces several extracellular cuticle-degrading proteases and evidence is consistent with one of these, pr1, which is a chymoelastase, being a determinant of pathogenicity. we have shown previously that pr1 production is regulated by both carbon catabolite and nitrogen metabolite repression and also by specific induction under derepressed conditions by insect cuticle. in the present work we have established that an enzymically released protein ... | 1994 | 7812455 |
| primary structure of locust flight muscle fatty acid binding protein. | the amino acid sequence of the fatty acid binding protein (fabp) from flight muscle of the locust, schistocerca gregaria, has been determined. the sequence of the n-terminal 39 amino acid residues, determined by automated edman degradation, was used to prepare a degenerate oligonucleotide that corresponded to amino acid residues 16-23. cdna coding for fabp was constructed from flight muscle mrna and amplified by the polymerase chain reaction using the degenerate oligonucleotide and an oligo dt-n ... | 1992 | 1497348 |
| the innervation of the closer muscle of the mesothoracic spiracle of the locust. | the closer muscle of the mesothoracic spiracle of the locust, schistocerca gregaria is innervated by two excitatory motoneurones and also by processes of a peripherally located neurosecretory cell. within the muscle, ultrastructural studies show the presence of two types of excitatory nerve terminal which differ in the content of dense cored vesicles and in their distribution. the ventral segment of the muscle is innervated predominantly by terminals with small clear vesicles and only an occasio ... | 1992 | 1440578 |
| neuropeptide-degrading endopeptidase activity of locust (schistocerca gregaria) synaptic membranes. | locust adipokinetic hormone (akh, pglu-leu-asn-phe-thr-pro-asn-trp-gly-thr-nh2) was used as the substrate to measure neuropeptide-degrading endopeptidase activity in neutral membranes from ganglia of the locust schistocerca gregaria. initial hydrolysis of akh at neural ph by peptidases of washed neural membranes generated pglu-leu-asn and phe-thr-pro-asn-trp-gly-thr-nh2 as primary metabolites, demonstrating that degradation was initiated by cleavage of the asn-phe bond. amastatin protected the c ... | 1988 | 3063256 |
| the distribution of bovine pancreatic polypeptide/fmrfamide-like immunoreactivity in the ventral nervous system of the locust. | the distribution of bovine pancreatic polypeptide (bpp) fmrfamide-like immunoreactivity is described in the ganglia of the ventral nerve cord and in the peripheral median nervous system of the locust, schistocerca gregaria. immunoreactive cell bodies occur in three regions of the thoracic ganglia: 1) two pairs of cells lie in the anterior of the ganglion ventral to the root of nerve 1 and the anterior ventral association centre; 2) a group of cells lies in the ventral midline at the level at whi ... | 1985 | 2579985 |
| further characterisation of the [35s]-tbps binding site of the gaba receptor complex in locust (schistocerca gregaria) ganglia membranes. | 1. using homogenates of supraoesophageal ganglia from locust we observed specific binding of [35s]-tbps which was linear with protein concentration up to 7 mg/ml, showed a ph optimum at ph 9.0 and was linear with nacl concentration up to 350 mm. 2. kinetic analysis of the binding showed positive cooperativity as a result of changes in on and off-rates with occupation of the binding site by the ligand. the apparent kd = 417 nm and bmax = 1083 fmol/mg of membrane protein were calculated using a co ... | 1989 | 2566451 |
| evasion of the haemocytic defence reaction of certain insects by larvae of hymenolepis diminuta (cestoda). | larvae of hymenolepis diminuta develop in the haemocoele of the beetles tribolium and tenebrio, and of the locust schistocerca gregaria, without being encapsulated by haemocytes. the mechanism of this evasion of the haemocytic defence reaction has been examined using various techniques. larvae grown in culture and injected into s. gregaria have a few or no haemocytes adherent even after 8h, although latex beads injected at the same time have been thickly encapsulated. this, and results of transp ... | 1976 | 967532 |
| effects of calcium ions and adenosine diphosphate on the activities of nad+-linked isocitrate dehydrogenase from the radular muscles of the whelk and flight muscles of insects. | 1. the activity of nad+-linked isocitrate dehydrogenase from the radular muscle of the whelk is higher than those in many vertebrate muscles and only slightly lower than in the flight muscles of insects. the enzyme activity from the whelk (buccinum undatum) is stable for several hours after homogenization of the radular muscle, whereas that from insect flight muscle is very unstable. consequently, the enzyme from the whelk muscle is suitable for a systematic investigation of the effects of ca2+ ... | 1976 | 182126 |
| aspergillosis in desert locust (schistocerka gregaria forsk). | fatal aspergillus flavus infection of desert locust at field station for investigations on locusts, bikaner, india, has been described. the infection appeared in the form of pinkish to brownish black patches with hardening of the affected regions, paralysis and twichings of the legs. the fungus was demonstrated in the lesions and was isolated from the diseased parts as well as from the air, floor and walls of the breeding cabin. the cool and humid conditions of the cabin favoured growth of the f ... | 1975 | 814463 |
| the dorsal, unpaired, median neurons of the locust metathoracic ganglion. | neurons having large cell bodies in the anterior dorsal median cluster in the metathoracic ganglion of the locust schistocerca gregaria and the grasshopper romalea microptera were studied by direct dye injection and reverse filling combined with elyctrical stimulation and recording. eight, possibly nine, are of the unpaired type, with a t branch leading into left and right axons that leave the ganglion to terminate in muscles. another six are probably paired, and may be interneurons. five of the ... | 1978 | 632816 |
| maximum activities and properties of glucose 6-phosphatase in muscles from vertebrates and invertebrates. | 1. the maximum catalytic activities of glucose 6-phosphatase were measured in a large number of muscles from vertebrates and invertebrates. the activities range from less than 0.1 to 8.0 mumol/min per g fresh wt. at 30 degrees c: the highest activity, observed in the flight muscle of the wasp (vespa vulgaris), is similar to that in rat liver. the hydrolytic activity was shown to be specific towards glucose 6-phosphate. 2. the ph optimum was 6.8 and the km was approx. 0.6 mm (flight muscle of a m ... | 1981 | 6275855 |
| pesticides for locust control. | the factors influencing the choice of insecticides for locust control are effectiveness, safety in use, relative cost, and the formulations available. the relative importance of these factors varies with the scale of control. in small scale control by farmers safety and simplicity are paramount and a bhc dust is commonly used, but in large scale control operations by specialized organizations more toxic formulations ultra-low-volume (u.l.v.) concentrates and methods of application requiring cons ... | 1979 | 43523 |
| calcium and sulphur in neurosecretory granules and calcium in mitochondria as determined by electron microscope x-ray microanalysis. | sections of neurosecretory cells fixed in glutaraldehyde and osmium tetroxide were studied by means of an emma-4 analytical microscope. secretory granules in neurosecretory cells of the corpus cardiacum and of the brain, both in the desert locust schistocerca and in the blowfly calliphora, as well as neurosecretory granules in posterior pituitaries of the frog rana and of the albino rat all contain a high concentration of calcium. a distinct sulphur peak was also a constant feature. in neurosecr ... | 1978 | 627026 |
| ecdysone 20-mono-oxygenase in the desert locust, schistocerca gregaria. | the enzyme catalysing the hydroxylation of ecdysone to 20-hydroxyecdysone, ecdysone 20-mono-oxygenase (ec 1.14.99.22), was investigated in the malpighian tubules of fifth-instar locusts, schistocerca gregaria. enzyme activity was optimal at 35 degrees c and ph 6.8-8.0. under these conditions the mono-oxygenase exhibited an apparent km for ecdysone of 7.1 x 10(-7) m, a maximal specific activity of 1.1 nmol/h per mg of protein and was competitively inhibited by 20-hydroxyecdysone with an apparent ... | 1984 | 6439188 |
| motile streptococci from the desert locust, schistocerca gregaria. | | 1966 | 5939389 |
| naturally occurring agglutinins against trypanosomatid flagellates in the haemolymph of insects. | in vitro studies of the behaviour of the trypanosomatid flagellates trypanosoma brucei and leishmania hertigi in the presence of cell-free haemolymph of locusts, schistocerca gregaria and cockroaches, periplaneta americana revealed the presence of parasite agglutinins. the range of normal values of agglutination titres was 2(-4) to 2(-13). physico-chemical treatment of haemolymph indicated that these agglutinins are protein or glycoprotein in nature and are only partially affected by heat treatm ... | 1984 | 6096791 |
| insect adipokinetic hormones. | peptides with adipokinetic (and usually carbohydrate-mobilizing) potency have been demonstrated in various insects, including locusta migratoria, schistocerca gregaria, manduca sexta, danaus plexippus and periplaneta americana. as far as characterized by now the adipokinetic factors are blocked peptides, consisting of eight to ten amino acid residues. in locusts the adipokinetic hormones are synthesized in the glandular lobe of the corpus cardiacum and released into the haemolymph in response to ... | 1985 | 3831971 |
| fmrfamide-like immunoreactivity in the metathoracic ganglion of the locust (schistocerca gregaria). | the distribution of fmrfamide-like immunoreactivity in the metathoracic ganglion of the locust, schistocerca gregaria, has been investigated in serial semithin transverse sections with the use of the peroxidase-antiperoxidase (pap) technique. the topographical distribution of approximately 120 immunopositive neurons was established. antiserum against bovine pancreatic polypeptide (bpp) stains the same ganglionic cells as fmrfamide-antiserum, yet this staining is largely blocked after preabsorpti ... | 1988 | 3409299 |
| occurrence of pseudomonas aeruginosa (schroeter) migula as a pathogenic bacterium of the desert locust, schistocerca gregaria (forskål). | | 1965 | 4953369 |
| acid phosphatases in the haemolymph of the desert locust, schistocerca gregaria, infected with the entomopathogenic fungus metarhizium anisopliae. | a comparison has been made between the effects of wounding, chemical stimulation of the immune system and fungal infection on acid phosphatase (acp) activity in the haemolymph of the desert locust, schistocerca gregaria. untreated control locusts had constitutive levels of acp. as a lysosomal enzyme, acp may have a role in autophagy and cell turn over as well as defence. injection of saline and beta-1,3-glucan caused significant increases in haemocyte and plasma acp. acp activity also increased ... | 2000 | 10844143 |
| fatty acid binding protein in locust and mammalian muscle. comparison of structure, function and regulation. | the flight muscle of adult desert locusts, schistocerca gregaria, contains a fatty acid binding protein (fabp) that is homologous to mammalian m-fabp (cardiac fabp. in spite of the evolutionary distance between invertebrates and vertebrates, locust muscle fabp is similar to cardiac fabp in its amino acid sequence, structure, and binding behavior. while cardiac fabp is present already in the prenatal period, locust fabp is an adult specific protein; its expression is directly linked to metamorpho ... | 1994 | 7553341 |
| concentrations of acetoacetate and 3-hydroxybutyrate in pigeon blood and desert locust haemolymph. | | 1971 | 5154039 |
| hemolymph transfer as an assay for immunorecognition in the cockroach periplaneta americana and the locust schistocerca gregaria. | a quantitative assay for measuring the number of hemocytic nodules formed in response to foreign particles and soluble molecules has been used, in the locust schistocerca and the cockroach periplaneta, to investigate the response to transferred hemolymph. xenogeneic test particles, rabbit neutrophil leukocytes, stimulate formation of nodules when injected into both insect species, compared with saline-injected controls. however, the number of nodules formed in the locust in response to cockroach ... | 1986 | 3952802 |
| mechanism of hydroxylation at c-22 during the biosynthesis of ecdysteroids in the locust schistocerca gregaria. | 1. the fates of the 22-pro-r and 22-pro-s hydrogen atoms of cholesterol during the biosynthesis of ecdysteroids in the ovaries of schistocerca gregaria were investigated. 2. two stereospecifically labelled cholesterol species, obtained by incubating 3r,2r- and 3r,2s-[2-14c, 2-3h]mevalonic acid with rat liver preparations, were administered, in turn, to maturing adult female locusts and the radiolabelled ecdysteroid conjugates isolated from the eggs. enzymic hydrolysis of the conjugates yielded f ... | 1982 | 7165737 |
| localization of octopaminergic neurones in insects. | this paper reviews data on the localization of octopaminergic neurons revealed by immunocytochemistry in insects, primarily the locusts schistocerca gregaria and locusta migratoria, cricket gryllus bimaculatus, and cockroach periplaneta americana. supporting evidence for their octopaminergic nature is mentioned where available. in orthopteran ventral ganglia, the major classes of octopamine-like immunoreactive (-li) neurones include: (1) efferent dorsal and ventral unpaired median (dum, vum) neu ... | 1995 | 7712064 |
| a simple method for immunofluorescent double staining with primary antisera from the same species. | we have developed a new double immunofluorescence technique by which two neuroactive substances in the same tissue section can be labeled with primary antisera raised in the same species. the optic lobes of the locust schistocerca gregaria were used as a model system to develop the staining procedure. fmrfamide-immunoreactive neurons were detected by rabbit antisera against fmrfamide and fitc-conjugated secondary antibodies. antibodies against the second peptide, pigment-dispersing hormone (pdh) ... | 1993 | 8450202 |
| molecular cloning of three distinct cdnas, each encoding a different adipokinetic hormone precursor, of the migratory locust, locusta migratoria. differential expression of the distinct adipokinetic hormone precursor genes during flight activity. | three distinct cdnas encoding the preproadipokinetic hormones i, ii, and iii (prepro-akh i, ii, and iii), respectively, of locusta migratoria have been isolated and sequenced. the three l. migratoria akh precursors have an overall architecture similar to that of other precursors of the akh/red pigment-concentrating hormone (rpch) family identified so far. the akh i and ii precursors of l. migratoria are highly homologous to the schistocerca gregaria and schistocerca nitans akh precursors. althou ... | 1995 | 7559443 |
| three-dimensional structure of the muscle fatty-acid-binding protein isolated from the desert locust schistocerca gregaria. | the three-dimensional structure of the fatty-acid-binding protein isolated from the flight muscle of the desert locust schistocerca gregaria has been solved and refined to a crystallographic r-value of 18.5% for all measured x-ray data from 30.0- to 2.2-a resolution. crystals employed in the investigation were grown from 2.6 to 2.8 m ammonium sulfate solutions, buffered at ph 7.5 and containing 2-5% 2-methyl-2,4-pentanediol. they belonged to the space group p2(1) with unit cell dimensions of a = ... | 1994 | 7918460 |
| analysis and modeling of time-dose-mortality of melanoplus sanguinipes, locusta migratoria migratorioides, and schistocerca gregaria (orthoptera: acrididae) from beauveria, metarhizium, and paecilomyces isolates from madagascar | a complementary log-log (cll) model was used to model time-dose-mortality relationships from bioassay tests of 26 fungal isolates mostly from madagascar, africa, against three acridid species, all referred to here as "grasshoppers." the fungal pathogens included 15 isolates of beauveria bassiana, 9 isolates of metarhizium flavoviridae, and 2 isolates of paecilomyces spp. grasshopper species tested included melanoplus sanguinipes, locusta migratoria migratorioides, and schistocerca gregaria. the ... | 1996 | 8812605 |
| distribution of schistoflrfamide-like immunoreactivity in the adult ventral nervous system of the locust, schistocerca gregaria. | schistoflrfamide (pdvdhvflrf-nh2) is one of the major endogenous neuropeptides of the fmrfamide family found in the nervous system of the locust, schistocerca gregaria. to gain insights into the potential physiological roles of this neuropeptide we have examined the distribution of schistoflrfamide-like immunoreactivity in the ventral nervous system of adult locusts by use of a newly developed n-terminally specific antibody. schistoflrfamide-like immunoreactivity in the ventral nerve cord is fou ... | 1995 | 7648627 |
| immunocytochemical mapping of serotonin and neuropeptides in the accessory medulla of the locust, schistocerca gregaria. | accumulating evidence suggests that pigment-dispersing hormone-immunoreactive neurons with ramifications in the accessory medulla of the insect brain are involved in circadian pacemaking functions. we have used immunocytochemical techniques to investigate the neurochemical organization of the accessory medulla in the locust schistocerca gregaria. local neurons with arborizations largely restricted to the accessory medulla are immunoreactive with antisera against serotonin, manduca sexta allatotr ... | 1995 | 8576441 |
| ryanoids change the permeability of potassium channels of locust (schistocerca gregaria) muscle. | the plasma membrane of locust skeletal muscle contains two types of k+ channel; a maxi, ca2+-activated 170 ps channel (bk channel) and an inward rectifier of 35 ps conductance (ik channel). the effects of ryanodine, 9,21-didehydroryanodine and 9,21-didehydroryanodol on these channels have been investigated. in the concentration domain 10(-9) m to 10(-5) m, ryanodine irreversibly induced a dose-dependent reduction of the reversal potential (vrev) of the channel currents, measured under physiologi ... | 1996 | 8764972 |
| purification of a novel, heat-stable serine protease inhibitor protein from ovaries of the desert locust, schistocerca gregaria. | a protease-inhibitor was isolated from mature ovaries of schistocerca gregaria by a combination of trypsin-affinity chromatography and reverse-phase high performance liquid chromatography. it was characterized by aminoterminal amino acid sequencing using edman degradation based automated microsequencing and by maldi-tof mass spectrometry. the n-terminal sequence (y)xaexdela(a)eey(y)q(q)x(i)(l)m (x being a cys, an irregular or modified amino acid) revealed no similarities with any other protease ... | 1997 | 9299512 |
| 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 ... | 2001 | 12770174 |
| successful parasitation of locusts by entomopathogenic nematodes is correlated with inhibition of insect phagocytes. | the entomopathogenic nematodes heterorhabditis megidis and steinernema feltiae turned out to be successful antagonists of the orthopteran insects locusta migratoria and schistocerca gregaria. the death rate of locusts maintained on nematode-inoculated sand was remarkably high. even dosages as low as one nematode per cubic centimeter of sand killed approximately 50% of the locusts within 10 days. the impact of parasitation on locusts' immune defense was closely investigated for l. migratoria para ... | 1999 | 10066395 |
| localization of soluble guanylyl cyclase alpha-subunit in identified insect neurons. | the distribution of soluble guanylyl cyclase in the brain of the locust schistocerca gregaria was analysed using antisera to a highly conserved region (x-peptide) of the drosophila soluble guanylyl cyclase alpha-subunit (sgcalpha). analysis of locust brain and locust eye homogenates in western blots using x-peptide antisera revealed specific staining of a approximately 65 kda band, which is similar to the expected molecular mass for a sgcalpha-subunit. sgcalpha-immunoreactivity was localized in ... | 1998 | 9685632 |
| characterization of a nicotinic acetylcholine receptor from the insect manduca sexta. | manduca sexta is a nicotine-insensitive insect, the larval form of which feeds on tobacco. it has been postulated that its nicotine insensitivity may reflect the presence of a modified nicotinic acetylcholine receptor whose alpha subunits lack the amino acid residues necessary for binding nicotine: we have performed ligand binding assays and molecular cloning to examine this hypothesis. [125i]alpha-bungarotoxin bound specifically to both larval and adult membranes, with kd values of 7.6 and 6.5 ... | 1998 | 9753155 |
| nitric oxide synthesis in locust olfactory interneurones | the brain of the locust schistocerca gregaria contains a nitric oxide synthase (nos) that has similar properties to mammalian neuronal nos. it catalyses the production of equimolar quantities of nitric oxide (no) and citrulline from l-arginine in a ca2+/calmodulin- and nadph-dependent manner and is inhibited by the nomega-nitro and nomega-monomethyl analogues of l-arginine. in western blots, an antiserum to the 160 kda rat cerebellar nos subunit recognises a locust brain protein with a molecular ... | 1995 | 9318598 |
| study on the occurrence of some microorganisms in locusts, schistocerca gregaria (forsk.) and their toxicological effects on laboratory animals. | | 1963 | 14121845 |
| purification, structural characterization, cloning and immunocytochemical localization of chemoreception proteins from schistocerca gregaria. | soluble low-molecular-mass protein isoforms were purified from chemosensory organs (antennae, tarsi and labrum) of the desert locust schistocerca gregaria. five genes encoding proteins of this group were amplified by pcr from cdnas of tarsi and sequenced. their expression products are polypeptide chains of 109 amino acids showing 40-50% sequence identity with putative olfactory proteins from drosophila melanogaster and cactoblastis cactorum. direct structural investigation on isoforms purified f ... | 1999 | 10411636 |
| immunocytochemistry of gaba in the central complex of the locust schistocerca gregaria: identification of immunoreactive neurons and colocalization with neuropeptides. | the central complex is a highly organized neuropil structure in the insect brain and plays a role in motor control and visual orientation. we describe the distribution of gamma-aminobutyric acid (gaba) immunostaining in the central complex of the locust schistocerca gregaria in an effort to analyze inhibitory neural circuits within this brain area. antisera against gaba and the gaba-synthesizing enzyme glutamic acid decarboxylase resulted in identical patterns of immunostaining. cell counts reve ... | 1999 | 10379833 |
| the role of destruxins in the pathogenicity of metarhizium anisopliae for three species of insect | the entomopathogenic fungus metarhizium anisopliae var anisopliae produces a family of cyclic peptide toxins, destruxins (dtx), both in culture and in vivo in mycosed insects. the contribution of these insecticidal toxins to the disease process has been investigated in the tobacco hornworm, manduca sexta (lepidoptera), the desert locust, schistocerca gregaria (orthoptera), and the vine weevil, otiorhynchus sulcatus (coleoptera). a significant negative correlation was found between the titer of d ... | 1999 | 10534408 |
| low molecular weight serine protease inhibitors from insects are proteins with highly conserved sequences. | a low molecular weight protease inhibitor peptide found in ovaries of the desert locust schistocerca gregaria (sgpi-2), was purified from plasma of the same locust and sequenced. it was named sgci. it was found active towards chymotrypsin and human leukocyte elastase. sgci was synthesized using a solid-phase procedure and the sequence of its reactive site for chymotrypsin was determined. compared with an inhibitor purified earlier from another locust species, the total sequence of sgci showed 88 ... | 2000 | 10696590 |
| proteinase inhibitors from desert locust, schistocerca gregaria: engineering of both p(1) and p(1)' residues converts a potent chymotrypsin inhibitor to a potent trypsin inhibitor. | two peptides, sgci and sgti, that inhibited chymotrypsin and trypsin, respectively, were isolated from the haemolymph of schistocerca gregaria. their primary structures were found to be identical with sgp-2 and sgp-1, two of a series of peptides isolated from ovaries of the same species (a. hamdaoui et al., febs lett. 422 (1998) 74-78). all these peptides are composed of 35-36 amino acid residues and contain three homologous disulfide bridges. the residues imparting specificity to sgci and sgti ... | 1999 | 10556568 |
| mechanism of c-2 hydroxylation during the biosynthesis of 20-hydroxyecdysone in ajuga hairy roots. | feeding synthetic [2beta-2h]- and [2alpha-2h]-cholesterols to the hairy roots of ajuga reptans var. atropurpurea and 2h-nmr analysis of the biosynthesized 20-hydroxyecdysone revealed that hydroxylation at c-2 proceeds with retention of configuration. feeding [2alpha,3alpha-2h2]cholesterol followed by 2h-nmr analysis of the 2,3,22-triacetate of the resulting 20-hydroxyecdysone ruled out a mechanism which involves a partial loss of the 2alpha-hydrogen. the steric course of c-2 hydroxylation in aju ... | 2000 | 10726854 |
| cloning and sequence of the gene encoding the muscle fatty acid binding protein from the desert locust, schistocerca gregaria. | muscle fatty acid binding protein (fabp) is a major cytosolic protein in flight muscle of the desert locust, schistocerca gregaria. fabp expression varies greatly during development and periods of increased fatty acid utilization, but the molecular mechanisms that regulate its expression are not known. in this study, the gene coding for locust muscle fabp was amplified by pcr and cloned, together with 1.2 kb of upstream sequence. the sequence coding for the 607 bp cdna is interrupted by two intr ... | 2001 | 11267894 |
| 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 ... | 2004 | 15326206 |
| acute toxicity of locust insecticides to two indigenous invertebrates from sahelian temporary ponds. | during desert locust plagues large amounts of insecticides are used for control operations. drift from these treatments and accidental overspraying may contaminate small surface waters such as temporary ponds. the present study describes methods for static acute toxicity tests with two abundant organisms that occur in temporary ponds in the african sahel region: the fairy shrimp streptocephalus sudanicus daday (branchiopoda, anostraca, streptocephalidae) and the backswimmer anisops sardeus herri ... | 2001 | 11161680 |
| adult survival, maturation, and reproduction of the desert locust schistocerca gregaria infected with the fungus metarhizium anisopliae var acridum. | studies were conducted with two different doses of metarhizium anisopliae var acridum to examine the effects on survival and reproductive potential of adult schistocerca gregaria under conditions that either limited thermoregulation or enabled optimal thermoregulation. adult s. gregaria infected with the fungal pathogen showed either a rapid and high mortality at relatively constant temperatures or a much reduced mortality and lengthened survival time when allowed to thermoregulate. mortality ra ... | 2001 | 11500087 |
| bacterial expression and conformational analysis of a chemosensory protein from schistocerca gregaria. | chemosensory proteins (csps) are a class of small, soluble proteins present at high concentrations in chemosensory organs of different insect species. several pieces of evidence suggest their involvement in carrying chemical messages from the environment to chemosensory receptors. however, a structural description of the mechanism of delivery has not been reported. in order to provide the first detailed conformational characterization of these molecules, we cloned a specific isoform (csp-sg4) fr ... | 2001 | 11532016 |
| 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 ... | 2005 | 15631618 |
| effects of temperature and relative humidity on sporulation of metarhizium anisopliae var. acridum in mycosed cadavers of schistocerca gregaria. | the effects of relative humidity (rh) and temperature on the sporulation of metarhizium anisopliae var. acridum on mycosed cadavers of desert locust, schistocerca gregaria, were assessed in the laboratory. quantitative assessments of conidial production over 10 days under constant conditions showed that sporulation was optimized at rh > 96% and at temperatures between 20 and 30 degrees c. under both these conditions >10(9) conidia/cadaver were produced. at 25 degrees c, conidial yield was maximi ... | 2001 | 11812107 |
| purification and sequence determination of a yellow protein from sexually mature males of the desert locust, schistocerca gregaria. | a yellow protein from abdominal cuticle of the desert locust, schistocerca gregaria, has been purified and its amino acid sequence determined. the yellow color comes from bound carotene, the protein is only deposited in the epidermis and cuticle of male locusts during their sexual maturation, and the deposition is dependent upon a sufficiently high titer of juvenile hormone. the sequence of the protein is atypical for a cuticular protein, but it has some similarity to a putative juvenile hormone ... | 2001 | 11583931 |
| 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 ... | 2004 | 15498959 |
| a novel fatty acid response element controls the expression of the flight muscle fabp gene of the desert locust, schistocerca gregaria. | in many tissues, fatty acid binding protein (fabp) expression is stimulated by exposure to elevated fatty acid levels. in contrast to the fabp genes expressed in other tissues, the molecular mechanisms that mediate the upregulation of the muscle fabp gene have not been elucidated. we have studied the expression of locust flight muscle fabp, a protein that is highly homologous to the mammalian h-fabps. a 130-bp promoter fragment of the locust gene, which includes a canonical tata box and several ... | 2001 | 11722577 |
| remarkable phylum selectivity of a schistocerca gregaria trypsin inhibitor: the possible role of enzyme-inhibitor flexibility. | a 35-mer polypeptide isolated from the hemolymph of desert locust schistocerca gregaria (sg) proved to be a canonical inhibitor of bovine trypsin (k(i) = 0.2 microm). despite having a trypsin-specific arginine at the primary specificity p(1) site, it inhibits bovine chymotrypsin almost as well (k(i) = 2 microm). furthermore, while the latter reactivity improves 10(4)-fold by the single replacement of p(1) arg by leu, changing p(1)' from lys to met only moderately improves trypsin affinity (k(i) ... | 2002 | 11831848 |
| 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 ... | 2005 | 16177887 |
| 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 ... | 2005 | 15879528 |
| 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) ... | 1998 | 12770158 |
| 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 ... | 2006 | 16777746 |
| 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 ... | 2000 | 12770206 |
| 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 ... | 2007 | 17166511 |
| 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 ... | 2000 | 12770225 |
| 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 ... | 1999 | 12770270 |
| role of cuticle-degrading proteases in the virulence of metarhizium spp. for the desert locust, schistocerca gregaria | the production of the subtilisin proteinase, pr1, and the trypsin-like enzyme, pr2, in liquid cultures of 19 isolates of metarhizium spp. was investigated. pr1 activity was generally observed 72 h after inoculation whilst pr2 activity was detected in most strains 48 h after inoculation. pr1 was partially purified from each isolate of metarhizium spp. the ability of this enzyme from each isolate to degrade different types of insect cuticle was investigated. the cuticle types used were manduca sex ... | 1998 | 9500951 |
| development of a bioassay employing the desert locust (schistocerca gregaria) for the detection of saxitoxin and related compounds in cyanobacteria and shellfish. | monitoring paralytic shellfish toxins (pst) in shellfish and freshwater cyanobacteria is largely dependent on the mouse bioassay. an alternative assay was devised using the desert locust schistocerca gregaria. the bioassay successfully identified the optimum extraction procedure for pst from cyanobacterial cells and was also suitable for screening acid extracts of shellfish flesh. these results demonstrate the potential of the locust bioassay for the routine screening of pst in a range of sample ... | 1998 | 9620590 |
| host-pathogen interactions in a varying environment: temperature, behavioural fever and fitness. | we demonstrate how variable temperatures, mediated by host thermoregulation and behavioural fever, critically affect the interaction between a host (the desert locust, schistocerca gregaria) and a pathogen (the fungus metarhizium anisopliae var. acridum). by means of behavioural thermoregulation, infected locusts can raise their body temperatures to fever levels. the adaptive value of this behaviour was examined using three thermal regimes wherein maximum body temperatures achievable were: (i) b ... | 2002 | 12184830 |
| 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 ... | 2003 | 12836967 |
| 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 ... | 2003 | 14550636 |
| 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 ... | 2003 | 14703905 |
| 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 ... | 2003 | 14560053 |
| 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. | 2003 | 15248675 |
| 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 ... | 2003 | 14618403 |
| 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 ... | 2004 | 14648100 |
| 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 ... | 2004 | 15154512 |
| 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 ... | 2003 | 15266906 |
| identification of a new tachykinin from the midgut of the desert locust, schistocerca gregaria, by esi-qq-oa-tof mass spectrometry. | this paper reports the purification of a tachykinin isoform from the midgut of the desert locust, schistocerca gregaria. one hundred locust midguts were extracted in an acidified methanolic solvent, after which three hplc column systems were used to obtain a pure peptide. a tachykinin immunoassay was used to monitor all collected fractions. after each purification step the purity of the sample was monitored by maldi-tof mass spectrometry. the pure peptide was sequenced by esi-qq-oa-tof mass spec ... | 1999 | 10581195 |
| oral infection of second-instar nymphs of schistocerca gregaria by metarrhizium anisopliae. | | 1966 | 5949417 |
| 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 ... | 2004 | 15759425 |
| humoral mechanisms in the immune response of insects to larvae of hymenolepis diminuta (cestoda). | previous work has shown that larvae of hymenolepis diminuta are not encapsulated by the haemocytes of the locust, schistocerca gregaria, but are encapsulated by haemocytes of the cockroach, periplaneta americana. the specificity of the cellular immune response in vivo, and of the agglutinating activity of the sera against vertebrate erythrocytes in vitro, is known to differ between the two species of insect. accordingly, the sera of each of these species was tested for its agglutinating activity ... | 1981 | 7301407 |
| 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 ... | 2004 | 15475302 |
| 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 ... | 2004 | 15604466 |
| 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 ... | 2005 | 15922357 |
| 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 ... | 2006 | 16384579 |
| 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 ... | 2011 | 21868406 |
| 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 ... | 2002 | 12443917 |
| neural mechanisms underlying behavior in the locust schistocerca gregaria. ii. integrative activity in metathoracic neurons. | | 2015 | 4703781 |
| 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 ... | 2011 | 22100291 |
| coping with crowds: density-dependent disease resistance in desert locusts. | parasite transmission generally exhibits some form of positive density dependence. thus, as population density increases, so too does the per capita risk of becoming infected. under such circumstances, natural selection should favor individuals that use cues associated with population density to determine the optimal allocation of resources to disease resistance mechanisms. as a consequence, individuals experiencing crowded conditions are predicted to be more resistant to parasites and pathogens ... | 2002 | 11960003 |
| characterization of a chemosensory protein (asp3c) from honeybee (apis mellifera l.) as a brood pheromone carrier. | chemosensory proteins (csps) are ubiquitous soluble small proteins isolated from sensory organs of a wide range of insect species, which are believed to be involved in chemical communication. we report the cloning of a honeybee csp gene called asp3c, as well as the structural and functional characterization of the encoded protein. the protein was heterologously secreted by the yeast pichia pastoris using the native signal peptide. asp3c disulfide bonds were assigned after trypsinolysis followed ... | 2002 | 12230571 |
| 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 ... | 2003 | 12655606 |
| 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 ... | 2006 | 16839309 |