Genomics, transcriptomics, and peptidomics of Daphnia pulex neuropeptides and protein hormones.

We report 43 novel genes in the water flea Daphnia pulex encoding 73 predicted neuropeptide and protein hormones as partly confirmed by RT-PCR. MALDI-TOF mass spectrometry identified 40 neuropeptides by mass matches and 30 neuropeptides by fragmentation sequencing. Single genes encode adipokinetic hormone, allatostatin-A, allatostatin-B, allatotropin, Ala(7)-CCAP, CCHamide, Arg(7)-corazonin, DENamides, CRF-like (DH52) and calcitonin-like (DH31) diuretic hormones, two ecdysis-triggering hormones, two FIRFamides, one insulin, two alternative splice forms of ion transport peptide (ITP), myosuppressin, neuroparsin, two neuropeptide-F splice forms, three periviscerokinins (but no pyrokinins), pigment dispersing hormone, proctolin, Met(4)-proctolin, short neuropeptide-F, three RYamides, SIFamide, two sulfakinins, and three tachykinins.

Transcriptome analysis of the desert locust central nervous system: production and annotation of a Schistocerca gregaria EST database.

Background: 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.

Pigment-dispersing hormone in Daphnia interneurons, one type homologous to insect clock neurons displaying circadian rhythmicity.

We report identification of a beta-type pigment-dispersing hormone (PDH) identical in two water flea species, Daphnia magna and Daphnia pulex. It has been identified by cloning of precursors, chromatographic isolation from tissue extracts followed by immunoassays and de novo-mass spectrometric sequencing. The peptide is restricted to a complex system of distinct interneurons in the brain and visual ganglia, but does not occur in neurosecretory cells projecting to neurohemal organs as in decapod crustaceans.

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.

In search for a common denominator for the diverse functions of arthropod corazonin: a role in the physiology of stress?

Corazonin (Crz) is an 11 amino acid C-terminally amidated neuropeptide that has been identified in most arthropods examined with the notable exception of beetles and an aphid. The Crz-receptor shares sequence similarity to the GnRH-AKH receptor family thus suggesting an ancestral function related to the control of reproduction and metabolism. In 1989, Crz was purified and identified as a potent cardioaccelerating agent in cockroaches (hence the Crz name based on "corazon", the Spanish word for "heart").

APRP, the second peptide encoded by the adipokinetic hormone gene(s), is highly conserved in evolution: a role in control of ecdysteroidogenesis?

Since the early days of cloning the first adipokinetic hormone (AKH) gene, researchers recognized that this gene also codes for a joining region and for a second peptide called adipokinetic hormone precursor related peptide (APRP). In species with more than one AKH gene, such as locusts, APRPs can form both homodimers and heterodimers. Database analysis showed that APRPs might belong to the ancient family of growth hormone releasing factor but they still are functionally orphan.

SIFamide illustrates the rapid evolution in Arthropod neuropeptide research.

This review is focussed on SIFamide. This neuropeptide was discovered as a result of an extensive purification process, typical for 20th century physiology, of an extract of 350,000 flesh flies. Our knowledge of SIFamide greatly expanded since the first publication in 1996.

Purification and characterization of an insulin-related peptide in the desert locust, Schistocerca gregaria: immunolocalization, cDNA cloning, transcript profiling and interaction with neuroparsin.

Members of the insulin superfamily are not restricted to vertebrates, but have also been identified in invertebrate species. In the current report, we present the characterization of Scg-insulin-related peptide (IRP), an insulin-related peptide in the desert locust, Schistocerca gregaria. This peptide was isolated from corpora cardiaca (CC) extracts by means of a high-performance liquid chromatography (HPLC)-based purification strategy.

Peptidomics: the integrated approach of MS, hyphenated techniques and bioinformatics for neuropeptide analysis.

MS is currently one of the most important analytical techniques in biological and medical research. ESI and MALDI launched the field of MS into biology. The performance of mass spectrometers increased tremendously over the past decades.

Development of a real-time PCR assay for measurement of yellow protein mRNA transcription in the desert locust Schistocerca gregaria: a basis for isolation of a peptidergic regulatory factor.

A major unresolved issue in insect endocrinology concerns the question of whether or not insects have sex hormones. Conclusive evidence in favor of the presence of such hormones awaits the establishment of appropriate bioassays in males. The cuticle of sexually mature males of the desert locust Schistocerca gregaria turns yellow in gregarious conditions only.

From the genome to the proteome: uncovering peptides in the Apis brain.

Neuropeptides, critical brain peptides that modulate animal behavior by affecting the activity of almost every neuronal circuit, are inherently difficult to predict directly from a nascent genome sequence because of extensive posttranslational processing. The combination of bioinformatics and proteomics allows unprecedented neuropeptide discovery from an unannotated genome. Within the Apis mellifera genome, we have inferred more than 200 neuropeptides and have confirmed the sequences of 100 peptides.

Actions of kinin peptides in the stomatogastric ganglion of the crab Cancer borealis.

To fully understand neuronal network operation, the influence of all inputs onto that network must be characterized. As in most systems, many neuronal and hormonal pathways influence the multifunctional motor circuits of the crustacean stomatogastric ganglion (STG), but the actions of only some of them are known. Therefore, we characterized the influence of the kinin peptide family on the gastric mill (chewing) and pyloric (filtering of chewed food) motor circuits in the STG of the crab Cancer borealis.

Annotation of novel neuropeptide precursors in the migratory locust based on transcript screening of a public EST database and mass spectrometry.

Background: For holometabolous insects there has been an explosion of proteomic and peptidomic information thanks to large genome sequencing projects. Heterometabolous insects, although comprising many important species, have been far less studied. The migratory locust Locusta migratoria, a heterometabolous insect, is one of the most infamous agricultural pests.

Cloning and characterization of a third isoform of corazonin in the honey bee Apis mellifera.

The precursor of the insect hormone corazonin has been cloned from the honey bee Apis mellifera. The precursor predicts a novel isoform of corazonin, pQTFTYSHGWTNamide, which was confirmed by tandem mass spectrometry. Although Apis corazonin differs only by a glutamine/threonine substitution from [His7]-corazonin, it is considerably less active in the dark color inducing assay on albino locusts.

Degradation profile of [His7]-corazonin in the hemolymph of the desert locust Schistocerca gregaria.

Degradation of the neuropeptide [His7]-corazonin, a key hormone in phase transition in locusts was studied using [3H][His7]-corazonin, RP-HPLC and mass spectrometry. After 4h incubation, 50 and 75% of [His7]-corazonin could still be found in hemolymph of gregarious and solitarious Schistocerca gregaria, respectively. Under in vivo conditions the half-life was 30 min.

Mass spectrometric analysis of head ganglia and neuroendocrine tissue of larval Galleria mellonella (Arthropoda, Insecta).

A brain-retrocerebral complex-subesophageal ganglion acidified methanolic extract of 100 larval Galleria mellonella (greater wax moth) was prepared for the isolation and identification of (neuro)peptides. To reduce sample complexity, the isolated peptides were roughly separated using a single, conventional chromatographic separation step. Subsequently, screening of these fractions with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in combination with nanoflow electrospray ionization quadrupole time-of-flight tandem mass spectrometry resulted in the identification of 12 lepidopteran peptides.

Fraenkel's pupariation factor identified at last.

Thirty-five years ago, Zdarek and Fraenkel demonstrated that nervous tissue extracts influenced development by accelerating pupariation in the grey flesh fly, Neobellieria bullata. We have now identified this pupariation factor as SVQFKPRLamide, designated Neb-pyrokinin-2 (Neb-PK-2). To achieve this, the central nervous system of N.

SIFamide is a highly conserved neuropeptide: a comparative study in different insect species.

Neb-LFamide or AYRKPPFNGSLFamide was originally purified from the grey flesh fly Neobellieria bullata as a myotropic neuropeptide. We studied the occurrence of this peptide and its isoforms in the central nervous system of different insect species by means of whole mount fluorescence immunohistochemistry, mass spectrometry, and data mining. We found that both sequence and immunoreactive distribution pattern are very conserved in the studied insects.

Bimanual coordination involving homologous and heterologous joint combinations: when lower stability is associated with higher flexibility.

Variability in behavior is often put in an unfavorable light as a marker of lack of skill. Here, we provide evidence that increased variability during preferred patterns of coordination is associated with higher flexibility in adopting new patterns. Twelve right-handed subjects performed cyclical bimanual flexion and extension patterns with four homologous and six heterologous joint combinations involving shoulder, elbow, wrist, and finger movements.

Diapausing Colorado potato beetles are devoid of short neuropeptide F I and II.

An extract of head ganglia and retrocerebral complexes of nondiapausing and diapausing Leptinotarsa decemlineata was prepared to characterize regulatory neuropeptides involved in adult diapause by using a differential peptidomics approach. To reduce sample complexity, both extracts were roughly separated by means of an identical chromatographic step. MALDI-TOF MS led to the identification of proctolin, an adipokinetic hormone, and short neuropeptide F I and II in the extract of nondiapausing beetles.

Neuropeptidomics of the grey flesh fly, Neobellieria bullata.

A peptidomics approach was applied to determine the peptides in the larval central nervous system of the grey flesh fly, Neobellieria bullata. Fractions obtained by high performance liquid chromatography were analysed by MALDI-TOF and ESI-Q-TOF mass spectrometry. This provided biochemical evidence for the presence of 18 neuropeptides, 11 of which were novel Neobellieria peptides.

Peptidomics.

Peptides occur in the whole animal kingdom, from the least evolved phyla with a very simple nervous system (coelenterates) to the highest vertebrates and are involved in most, if not all, physiological processes in animals. Knowing the amino acid sequence of peptide hormones or neurotransmitters is important since this allows for synthesis of large quantities of peptides to perform further functional analysis. Immunocytochemistry, radioimmunoassays (RIA), enzyme-linked immunosorbant assays (ELISA) and mass spectrometry can then provide information on the temporal and spatial distribution and quantification of the (neuro)peptide.

Neurotoxic and neurobehavioral effects of kynurenines in adult insects.

Kynurenines are endogenous metabolites of tryptophan, which are studied extensively in vertebrates with respect to their etiological role in the pathology of various neurodegenerative disorders. In insects, metabolites of the kynurenic pathway are present in peak concentrations in the hemolymph of holometabolic species during pupation and just before eclosion. Unlike in larvae, these compounds cause severe motor dysfunction in adult species.

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).