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Artificial intelligence (AI) uses sophisticated algorithms to "learn" from large volumes of data. This could be used to optimise recruitment of blood donors through predictive modelling of future blood supply, based on previous donation and transfusion demand. We sought to assess utilisation of predictive modelling and AI blood establishments (BE) and conducted predictive modelling to illustrate its use. A BE survey of data modelling and AI was disseminated to the International Society of Blood transfusion members. Additional anonymzed data were obtained from Italy, Singapore and the United States (US) to build predictive models for each region, using January 2018 through August 2019 data to determine likelihood of donation within a prescribed number of months. Donations were from March 2020 to June 2021. Ninety ISBT members responded to the survey. Predictive modelling was used by 33 (36.7%) respondents and 12 (13.3%) reported AI use. Forty-four (48.9%) indicated their institutions do not utilise predictive modelling nor AI to predict transfusion demand or optimise donor recruitment. In the predictive modelling case study involving three sites, the most important variable for predicting donor return was number of previous donations for Italy and the US, and donation frequency for Singapore. Donation rates declined in each region during COVID-19. Throughout the observation period the predictive model was able to consistently identify those individuals who were most likely to return to donate blood. The majority of BE do not use predictive modelling and AI. The effectiveness of predictive model in determining likelihood of donor return was validated; implementation of this method could prove useful for BE operations.
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The author's middle name is missed out in the original publication of the article [1]. The correct coauthor's name is Tobias J. Erb.
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BACKGROUND: The biological degradation of plastics is a promising method to counter the increasing pollution of our planet with artificial polymers and to develop eco-friendly recycling strategies. Polyethylene terephthalate (PET) is a thermoplast industrially produced from fossil feedstocks since the 1940s, nowadays prevalently used in bottle packaging and textiles. Although established industrial processes for PET recycling exist, large amounts of PET still end up in the environment-a significant portion thereof in the world's oceans. In 2016, Ideonella sakaiensis, a bacterium possessing the ability to degrade PET and use the degradation products as a sole carbon source for growth, was isolated. I. sakaiensis expresses a key enzyme responsible for the breakdown of PET into monomers: PETase. This hydrolase might possess huge potential for the development of biological PET degradation and recycling processes as well as bioremediation approaches of environmental plastic waste. RESULTS: Using the photosynthetic microalga Phaeodactylum tricornutum as a chassis we generated a microbial cell factory capable of producing and secreting an engineered version of PETase into the surrounding culture medium. Initial degradation experiments using culture supernatant at 30 °C showed that PETase possessed activity against PET and the copolymer polyethylene terephthalate glycol (PETG) with an approximately 80-fold higher turnover of low crystallinity PETG compared to bottle PET. Moreover, we show that diatom produced PETase was active against industrially shredded PET in a saltwater-based environment even at mesophilic temperatures (21 °C). The products resulting from the degradation of the PET substrate were mainly terephthalic acid (TPA) and mono(2-hydroxyethyl) terephthalic acid (MHET) estimated to be formed in the micromolar range under the selected reaction conditions. CONCLUSION: We provide a promising and eco-friendly solution for biological decomposition of PET waste in a saltwater-based environment by using a eukaryotic microalga instead of a bacterium as a model system. Our results show that via synthetic biology the diatom P. tricornutum indeed could be converted into a valuable chassis for biological PET degradation. Overall, this proof of principle study demonstrates the potential of the diatom system for future biotechnological applications in biological PET degradation especially for bioremediation approaches of PET polluted seawater.
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Burkholderiales/metabolismo , Hidrolases/metabolismo , Microalgas/metabolismo , Polietilenotereftalatos/metabolismo , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Biologia Marinha , Microbiologia da ÁguaRESUMO
BACKGROUND: The red flour beetle Tribolium castaneum is an emerging insect model organism representing the largest insect order, Coleoptera, which encompasses several serious agricultural and forest pests. Despite the ecological and economic importance of beetles, most insect olfaction studies have so far focused on dipteran, lepidopteran, or hymenopteran systems. RESULTS: Here, we present the first detailed morphological description of a coleopteran olfactory pathway in combination with genome-wide expression analysis of the relevant gene families involved in chemoreception. Our study revealed that besides the antennae, also the mouthparts are highly involved in olfaction and that their respective contribution is processed separately. In this beetle, olfactory sensory neurons from the mouthparts project to the lobus glomerulatus, a structure so far only characterized in hemimetabolous insects, as well as to a so far non-described unpaired glomerularly organized olfactory neuropil in the gnathal ganglion, which we term the gnathal olfactory center. The high number of functional odorant receptor genes expressed in the mouthparts also supports the importance of the maxillary and labial palps in olfaction of this beetle. Moreover, gustatory perception seems equally distributed between antenna and mouthparts, since the number of expressed gustatory receptors is similar for both organs. CONCLUSIONS: Our analysis of the T. castaneum chemosensory system confirms that olfactory and gustatory perception are not organotopically separated to the antennae and mouthparts, respectively. The identification of additional olfactory processing centers, the lobus glomerulatus and the gnathal olfactory center, is in contrast to the current picture that in holometabolous insects all olfactory inputs allegedly converge in the antennal lobe. These findings indicate that Holometabola have evolved a wider variety of solutions to chemoreception than previously assumed.
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Besouros/genética , Perfilação da Expressão Gênica/métodos , Animais , Células Quimiorreceptoras/metabolismo , Besouros/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismoRESUMO
The genus Singerocybe (Tricholomataceae, Agaricales, Basidiomycota) has been the subject of controversy since its proposal in 1988. Its taxonomic foundation, species circumscription and geographical distribution have not yet been examined with molecular sequence data. In this study phylogenetic analyses on this group of fungi were conducted based on collections from Europe, eastern Asia, southern Asia, North America and Australia, with four nuclear markers, ITS, nrLSU, tef1-α and rpb2. Molecular phylogenetic analyses, together with morphological observations, strongly support Singerocybe as a monophyletic group and identify the vesicles in the pileal and stipe cuticle as a synapomorphy of this genus. Seven species are recognized in the genus, including one new species and four new combinations. Clitocybe trogioides and Clitocybe trogioides var. odorifera are synonyms of Singerocybe humilis and Singerocybe alboinfundibuliformis respectively. Most of these species are geographically restricted in their distributions. Furthermore our study expands the distribution range of Singerocybe from the North Temperate Zone to Australia (Tasmania) and tropical southern Asia.
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Agaricales/classificação , Agaricales/citologia , Agaricales/genética , Agaricales/isolamento & purificação , Ásia , Austrália , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Europa (Continente) , Evolução Molecular , Ásia Oriental , Carpóforos , Proteínas Fúngicas/genética , Dados de Sequência Molecular , América do Norte , Filogenia , RNA Polimerase II/genética , Análise de Sequência de DNA , Esporos FúngicosRESUMO
The adult musculature in D. melanogaster forms during metamorphosis. Much is known about the flight and leg musculature, but not about the muscles surrounding the male reproductive tract. The inner genitalia of males consist of the testes, which emerge from the gonads; the remaining genital organs, i.e., paragonia (or accessory glands), ejaculatory duct, sperm pump, and seminal vesicles, develop out of the genital imaginal disc. We analyzed the myoblasts forming the muscle layers of these organs. In myoblasts derived from the genital imaginal disc, the regulatory region of the transcription factor DMef2 is active. DMef2 is also needed for specification and differentiation of embryonic and adult myoblasts. We could discriminate three different muscle types: (i) multinucleated muscles that resemble vertebrate smooth muscles surround the testes, (ii) multinucleated muscles that resemble striated muscles comprises seminal vesicles and the sperm pump, and (iii) mononucleated striated musculature encloses the paragonia and ejaculatory duct. Members of the immunoglobulin superfamily involved in embryonic myogenesis, Dumbfounded (Duf) and Sticks and Stones (Sns), were also expressed in the genital imaginal disc, in the muscle sheath of the testes during muscle differentiation and in the secretory secondary cells, which are part of the binucleated epithelia enclosing the paragonia.
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Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Genitália Masculina/crescimento & desenvolvimento , Metamorfose Biológica/fisiologia , Desenvolvimento Muscular/fisiologia , Músculo Liso/crescimento & desenvolvimento , Músculo Estriado/crescimento & desenvolvimento , Animais , Diferenciação Celular/fisiologia , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Genitália Masculina/ultraestrutura , Imunoglobulinas/metabolismo , Imuno-Histoquímica , Masculino , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Varredura , Proteínas Musculares/metabolismo , Mioblastos/citologia , Mioblastos/ultraestruturaRESUMO
OBJECTIVE: Molecular testing determines D antigen status when abnormal serologic results are observed. Molecular testing is routinely batched, resulting in longer turnaround time for abnormal D status resolution. During the interim, obstetric patients with questionable/uninterpretable and weak D typing results by serology, per the immunohematology reference laboratory (IRL) policy, will receive RhD negative blood. This study aimed to determine whether serology results achieved a concordance. METHODS: Six hospitals provided samples to the IRL (first IRL) for RhD status by DNA. De-identified samples were sent for serology RhD (second IRL). A concordance ofâ ≥80% was acceptable. RESULTS: Forty-nine samples were evaluated. Results were concordant (65.3% [32/49]) and discordant (34.7% [17/49]). This is significantly lower than clinically acceptable 80% (zâ =â 2.57, Pâ <â .05). The turnaround-time was 3.0 hours for serology and 4.4 days for molecular evaluation. CONCLUSION: Due to a low concordance, serology could not be used in place of molecular testing.
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Testes Hematológicos , Hospitais , Feminino , Gravidez , Humanos , Técnicas de Diagnóstico Molecular , Testes de Função TireóideaRESUMO
The paired antennal lobes were long considered the sole primary processing centers of the olfactory pathway in holometabolous insects receiving input from the olfactory sensory neurons of the antennae and mouthparts. In hemimetabolous insects, however, olfactory cues of the antennae and palps are processed separately. For the holometabolous red flour beetle Tribolium castaneum, we could show that primary processing of the palpal and antennal olfactory input also occurs separately and at distinct neuronal centers. While the antennal olfactory sensory neurons project into the antennal lobes, those of the palps project into the paired glomerular lobes and the unpaired gnathal olfactory center. Here we provide an extended analysis of the palpal olfactory pathway by combining scanning electron micrographs with confocal imaging of immunohistochemical staining and reporter expression identifying chemosensory and odorant receptor-expressing neurons in the palpal sensilla. In addition, we extended the anatomical characterization of the gnathal olfactory center by 3D reconstructions and investigated the distribution of several neuromediators. The similarities in the neuromediator repertoire between antennal lobes, glomerular lobes, and gnathal olfactory center underline the role of the latter two as additional primary olfactory processing centers.
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Tomato (Solanum lycopersicum L.) roots from four different crop sites in Colombia were surface sterilized and 51 fungal isolates were obtained and conserved for further analysis. Based on microscopical observations and growth characteristics, 20 fungal isolates corresponded to genus Fusarium, six presented asexual conidia different from Fusarium, eight were sterile mycelia, seven of which had dark septate hyphae and 17 did not continue to grow on plates after being recovered from conservation. Growth on different media, detailed morphological characterization and ITS region sequencing of the six sporulating and eight sterile isolates revealed that they belonged to different orders of Ascomycota and that the sterile dark septate endophytes did not correspond to the well known Phialocephala group. Interactions of nine isolates with tomato plantlets were assessed in vitro. No effect on shoot development was revealed, but three isolates caused brown spots in roots. Colonization patterns as analyzed by confocal microscopy differed among the isolates and ranged from epidermal to cortical penetration. Altogether 11 new isolates from root endophytic fungi were obtained, seven of which showed features of dark septate endophytes. Four known morphotypes were represented by five isolates, while six isolates belonged to five morphotypes of putative new unknown species.
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Ascomicetos/crescimento & desenvolvimento , Solanum lycopersicum/microbiologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases , Colômbia , Produtos Agrícolas/microbiologia , DNA Intergênico/genética , DNA Espaçador Ribossômico/genética , Fusarium/crescimento & desenvolvimento , Hifas/crescimento & desenvolvimento , Filogenia , Raízes de Plantas/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Simbiose/genéticaRESUMO
Guanine nucleotide exchange factors (GEF) of the BRAG subfamily activate small Arf GTPases, which are pivotal regulators of intracellular membrane traffic and actin dynamics. Consequently, BRAG proteins have been implicated to regulate the surface levels of adhesive and signaling receptors. However, not much is known about the mechanism leading to the regulation of these surface proteins. In this study we found that the Drosophila BRAG GEF Schizo interacts physically with the Abl-interactor (Abi). schizo mutants display severe defects in myoblast fusion during syncytial muscle formation and show increased amounts of the cell adhesion protein N-cadherin. We demonstrate that the schizo myoblast fusion phenotype can be rescued by the expression of the Schizo GEF (Sec7) and membrane-binding (pleckstrin homology) domain. Furthermore, the expression of the Sec7-PH domain in a wild-type background decreases the amounts of N-cadherin and impairs myoblast fusion. These findings support the notion that the Sec7-PH domain serves as a constitutive-active form of Schizo. Using a yeast-two hybrid assay, we show that the SH3 domain of Abi interacts with the N-terminal region of Schizo. This region is also able to bind to the cytodomain of the cell adhesion molecule N-cadherin. To shed light on the function of Schizo and Abi in N-cadherin removal, we employed epistasis experiments in different developmental contexts of Drosophila. These studies point towards a new model for the regulation of Schizo. We propose that the binding of Abi to the N-terminal part of Schizo antagonizes Schizo function to inhibit N-cadherin removal.
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Plastic pollution has become a serious issue on Earth. Although efficient industrial recycling processes exist, a significant fraction of plastic waste still ends up in nature, where it can endure for centuries. Slow mechanical and chemical decay lead to the formation of micro- and nanoplastics, which are washed from land into rivers and finally end up in the oceans. As such particles cannot be efficiently removed from the environment, biological degradation mechanisms are highly desirable. Several enzymes have been described that are capable of degrading certain plastic materials such as polyethylene terephthalate (PET). Such enzymes have a huge potential for future biotechnology applications. However, they require model systems that can be efficiently adapted to very specific conditions. Here, we present detailed instructions, how to convert the model diatom Phaeodactylum into a solar-fueled microbial cell factory for PETase expression, resulting in a whole cell catalyst for PET degradation at moderate temperatures under saltwater conditions.
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Microalgas , Polietilenotereftalatos , Oceanos e Mares , PlásticosRESUMO
Plant pathogenic fungi colonizing living plant tissue secrete a cocktail of effector proteins to suppress plant immunity and reprogramme host cells. Although many of these effectors function inside host cells, delivery systems used by pathogenic bacteria to translocate effectors into host cells have not been detected in fungi. Here, we show that five unrelated effectors and two membrane proteins from Ustilago maydis, a biotrophic fungus causing smut disease in corn, form a stable protein complex. All seven genes appear co-regulated and are only expressed during colonization. Single mutants arrest in the epidermal layer, fail to suppress host defence responses and fail to induce non-host resistance, two reactions that likely depend on translocated effectors. The complex is anchored in the fungal membrane, protrudes into host cells and likely contacts channel-forming plant plasma membrane proteins. Constitutive expression of all seven complex members resulted in a surface-exposed form in cultured U. maydis cells. As orthologues of the complex-forming proteins are conserved in smut fungi, the complex may become an interesting fungicide target.
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Basidiomycota/metabolismo , Basidiomycota/patogenicidade , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Virulência , Zea mays/microbiologiaRESUMO
A big challenge of the 21st century is to cope with the huge amounts of plastic waste on Earth. Especially the oceans are heavily polluted with plastics. To counteract this issue, biological (enzymatic) plastic decomposition is increasingly gaining attention. Recently it was shown that polyethylene terephthalate (PET) can be degraded in a saltwater-based environment using bacterial PETase produced by a marine diatom. At moderate temperatures, plastic biodegradation is slow and requires sensitive methods for detection, at least at initial stages. However, conventional methods for verifying the plastic degradation are either complex, expensive, time-consuming or they interfere with the degradation process. Here, we adapt lensless digital holographic microscopy (LDHM) as a new application for efficiently monitoring enzymatic degradation of a PET glycol copolymer (PETG). LDHM is a cost-effective, compact and sensitive optical method. We demonstrate enzymatic PETG degradation over a time course of 43 days employing numerical analysis of LDHM images.
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Microscopia , Plásticos , Bactérias , Biodegradação Ambiental , Oceanos e MaresRESUMO
The fungal genus Strobilurus belongs to Physalacriaceae and contains approximately 11 species worldwide. Species of this genus grow and reproduce on cones of various conifers, seed pods or fruits of Magnolia and Liquidambar, and branches and wood of conifers. Previous studies focused mainly on samples from Europe and North America. And no genus-specific phylogenetic analysis has been carried out to date. The monophyly, degree of species diversity and substrate specificity, and overall distribution patterns are addressed here using morphological and molecular evidence. The authors collected samples of Strobilurus from much of its known distribution ranges and carried out morphological observations and multilocus phylogenetic analyses using five molecular markers. The results show that Strobilurus is a monophyletic group but may exclude one species, S. ohshimae. A total of 13 species was identified, with two, S. orientalis and S. pachycystidiatus, described as new from China. Several species were shown to be specific to certain substrates, whereas a few less so. Biogeographic analyses indicated that historical exchanges of species between East Asia, Europe, and North America, later vicariance events, and substrate specificity have contributed jointly to diversification of Strobilurus.
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Agaricales/classificação , Biodiversidade , Filogenia , Agaricales/genética , Agaricales/isolamento & purificação , Evolução Biológica , China , DNA Fúngico/genética , DNA Ribossômico/genética , Europa (Continente) , Ásia Oriental , Genes Fúngicos/genética , Variação Genética , Especificidade de Hospedeiro , América do Norte , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
The arbuscular mycorrhiza (AM) is characterized by specific morphological structures of the fungus and the plant and by physiological adaptations which are mostly beneficial for both partners of the symbiosis. This review describes approaches to study the molecular basis of the interaction. RNA accumulation patterns have been monitored in Pisum sativum to analyse the plant response to arbuscule development. In a direct approach, the Mtha1 gene from Medicago truncatula was cloned which is expressed in arbusculated cells of M. truncatula. The gene putatively encodes an H(+)-ATPase involved in the improved plant nutrition during mycorrhization. Finally, a tripartite system between M. truncatula, Glomus mosseae and Aphanomyces euteiches was established, in order to study bioprotection. Analysis of the transcriptome has been started to analyse the interaction between the plant, the pathogen and the AM fungus.
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Regulação da Expressão Gênica de Plantas , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Micorrizas/ultraestrutura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , SimbioseRESUMO
Purple Laccaria are ectomycorrhizal basidiomycetes associated with temperate forests all over the Northern Hemisphere in at least two taxa: Laccaria amethysteo-occidentalis in North America, and L. amethystina complex in Eurasia, as shown by Vincenot et al. (2012). Here, we combine a further study of the genetic structure of L. amethystina populations from Europe to southwestern China and Japan, using neutral Single Sequence Repeat (SSR; microsatellite) markers; and a systematic description of two novel Asian species, namely Laccaria moshuijun and Laccaria japonica, based on ecological, morphological, and molecular criteria (rDNA sequences). Population genetics provides evidence of the ancient isolation of three regional groups, with strong signal for speciation, and suggests a centre of origin of modern populations closest to present-day Chinese populations. Phylogenetic analyses confirm speciation at the molecular level, reflected in morphological features: L. moshuijun samples (from Yunnan, China) display strongly variable cheilocystidia, while L. japonica samples (from Japan) present distinctive globose to subglobose spores and clavate cheilocystidia. This study of a species complex primarily described with an extremely wide ecological and geographical range sheds new light on the biodiversity and biogeography of ectomycorrhizal fungi.
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Laccaria/classificação , Laccaria/isolamento & purificação , Repetições de Microssatélites , Filogenia , Filogeografia , China , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Europa (Continente) , Japão , Laccaria/citologia , Laccaria/genética , Microscopia , Análise de Sequência de DNARESUMO
Adult age-specific colorectal cancer incidence rates increase exponentially from maturity, reach a maximum, then decline in extreme old age. Armitage and Doll (1) postulated that the exponential increase resulted from "n" mutations occurring throughout adult life in normal "cells at risk" that initiated the growth of a preneoplastic colony in which subsequent "m" mutations promoted one of the preneoplastic "cells at risk" to form a lethal neoplasia. We have reported cytologic evidence that these "cells at risk" are fetal/juvenile organogenic, then preneoplastic metakaryotic stem cells. Metakaryotic cells display stem-like behaviors of both symmetric and asymmetric nuclear divisions and peculiarities such as bell shaped nuclei and amitotic nuclear fission that distinguish them from embryonic, eukaryotic stem cells. Analyses of mutant colony sizes and numbers in adult lung epithelia supported the inferences that the metakaryotic organogenic stem cells are constitutively mutator/hypermutable and that their contributions to cancer initiation are limited to the fetal/juvenile period. We have amended the two-stage model of Armitage and Doll and incorporated these several inferences in a computer program CancerFit v.5.0. We compared the expectations of the amended model to adult (15-104 years) age-specific colon cancer rates for European-American males born 1890-99 and observed remarkable concordance. When estimates of normal colonic fetal/juvenile APC and OAT gene mutation rates (â¼2-5 × 10(-5) per stem cell doubling) and preneoplastic colonic gene loss rates (â¼8 × 10(-3)) were applied, the model was in accordance only for the values of n = 2 and m = 4 or 5.
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Microtubules are necessary for fusion and elongation of vertebrate muscle cells. In Drosophila, several isoforms of ß-Tubulin, the functional subunit of microtubules, are expressed in different tissues of the developing embryo, while solely the ß3-Tubulin isoform is detected in large amounts during differentiation of the somatic and visceral musculature. Here we show the unexpected result that all mesodermal tissues develop correctly in ß3-Tubulin loss of function mutants. Furthermore, we show that ß2-Tubulin transcripts are not detectable in embryos and an exceptional zygotic ß1-Tubulin expression in ß3-Tubulin mutants cannot be observed. Nevertheless, a maternally contributed ß1-Tubulin-GFP fusion protein (from protein trap collection, Buszczak et al., 2007, Genetics 175, 1505-1531) acts in a dominant negative way, disturbing embryonic development from early stages on. This effect can be observed to the same extent in a zygotic ß3-Tubulin mutant situation. Our results indicate that the maternally supplied ß1-Tubulin based microtubule network is sufficient for myoblast fusion, myotube elongation and sarcomere formation both during visceral and somatic muscle development in Drosophila embryogenesis.
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Drosophila/embriologia , Embrião não Mamífero/embriologia , Microtúbulos/metabolismo , Proteínas Mutantes/metabolismo , Mioblastos/metabolismo , Sarcômeros/metabolismo , Tubulina (Proteína)/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Drosophila/metabolismo , Embrião não Mamífero/metabolismo , Microtúbulos/ultraestrutura , Morfogênese/genética , Proteínas Mutantes/genética , Mioblastos/ultraestrutura , Sarcômeros/ultraestrutura , Tubulina (Proteína)/genéticaRESUMO
The larvae of the cabbage root fly induce serious damage to cultivated crops of the family Brassicaceae. We here report the biochemical characterisation of neuropeptides from the central nervous system and neurohemal organs, as well as regulatory peptides from enteroendocrine midgut cells of the cabbage maggot. By LC-MALDI-TOF/TOF and chemical labelling with 4-sulfophenyl isothiocyanate, 38 peptides could be identified, representing major insect peptide families: allatostatin A, allatostatin C, FMRFamide-like peptides, kinin, CAPA peptides, pyrokinins, sNPF, myosuppressin, corazonin, SIFamide, sulfakinins, tachykinins, NPLP1-peptides, adipokinetic hormone and CCHamide 1. We also report a new peptide (Yamide) which appears to be homolog to an amidated eclosion hormone-associated peptide in several Drosophila species. Immunocytochemical characterisation of the distribution of several classes of peptide-immunoreactive neurons and enteroendocrine cells shows a very similar but not identical peptide distribution to Drosophila. Since peptides regulate many vital physiological and behavioural processes such as moulting or feeding, our data may initiate the pharmacological testing and development of new specific peptide-based protection methods against the cabbage root fly and its larva.
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Dípteros/metabolismo , Células Enteroendócrinas/metabolismo , Proteínas de Insetos/metabolismo , Neurônios/metabolismo , Hormônios Peptídicos/metabolismo , Proteômica , Animais , Brassica/parasitologia , Dípteros/citologia , Células Enteroendócrinas/citologia , Larva/citologia , Larva/metabolismo , Raízes de Plantas/parasitologiaRESUMO
Metamorphosis is a fundamental developmental process and has been intensively studied for various neuron types of Drosophila melanogaster. However, detailed accounts of the fate of identified peptidergic neurons are rare. We have performed a detailed study of the larval morphology and pupal remodelling of identified peptidergic neurons, the CAPA-expressing Va neurons of D. melanogaster. In the larva, Va neurons innervate abdominal median and transverse nerves that are typically associated with perisympathetic organs (PSOs), major neurohaemal release sites in insects. Since median and transverse nerves are lacking in the adult, Va neurites have to undergo substantial remodelling during metamorphosis. We have examined the hitherto uncharacterised gross morphology of the thoracic PSOs and the abdominal median and transverse nerves by scanning electron microscopy and found that the complete reduction of these structures during metamorphosis starts around pupal stage P7 and is completed at P9. Concomitantly, neurite pruning of the Va neurons begins at P6 and is preceded by the high expression of the ecdysone receptor (EcR) subtype B1 in late L3 larvae and the first pupal stages. New neuritic outgrowth mainly occurs from P7-P9 and coincides with the expression of EcR-A, indicating that the remodelling of the Va neurons is under ecdysteroid control. Immunogold-labelling has located the CAPA peptides to large translucent vesicles, which are released from the transverse nerves, as suggested by fusion profiles. Hence, the transverse nerves may serve a neurohaemal function in D. melanogaster.