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[PMID]: 29182502 [Au] Autor: Kingston ACN; Chappell DR; Miller HV; Lee SJ; Speiser DI [Ti] Título: Expression of G Proteins in the Eyes and Parietovisceral Ganglion of the Bay Scallop Argopecten irradians. [So] Source: Biol Bull;233(1):83-95, 2017 Aug. [Is] ISSN: 1939-8697 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: A multitude of image-forming eyes are spread across the bodies of certain invertebrates. Recent efforts have characterized how these eyes function, but less progress has been made toward describing the neural structures associated with them. Scallops, for example, have a distributed visual system that includes dozens of eyes whose optic nerves project to the lateral lobes of the parietovisceral ganglion (PVG). To identify sensory receptors and chemical synapses associated with the scallop visual system, we studied the expression of four G protein α subunits (Gα , Gα , Gα , and Gα ) in the eyes and PVG of the bay scallop Argopecten irradians (Lamarck, 1819). In the eyes of A. irradians, we noted expression of Gα by the ciliary photoreceptors of the distal retina, expression of Gα by the rhabdomeric photoreceptors of the proximal retina, and the expression of Gα and Gα by the cells of the cornea; we did not, however, detect expression of Gα or Gα in the eyes. In the PVG of A. irradians, we noted widespread expression of Gα , Gα , and Gα . The expression of Gα was limited to fine neurites in the lateral and ventral central lobes, as well as large unipolar neurons in the dorsal central lobes. Our findings suggest that light detection by the eyes of A. irradians is conferred primarily by photoreceptors that express Gα or Gα , that the corneal cells of scallops may contain sensory receptors and/or receive neural input, and that G protein labeling is useful for visualizing substructures and identifying specific populations of cells within the nervous systems of invertebrates. [Mh] Termos MeSH primário: Subunidades alfa de Proteínas de Ligação ao GTP/genética Expressão Gênica Pectinidae/genética [Mh] Termos MeSH secundário: Animais Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo Gânglios dos Invertebrados/fisiologia Perfilação da Expressão Gênica Pectinidae/citologia Células Fotorreceptoras de Invertebrados/fisiologia [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (GTP-Binding Protein alpha Subunits) [Em] Mês de entrada: 1801 [Cu] Atualização por classe: 180111 [Lr] Data última revisão: 180111 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 171129 [St] Status: MEDLINE [do] DOI: 10.1086/694448

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[PMID]: 28807895 [Au] Autor: Sasidharan V; Marepally S; Elliott SA; Baid S; Lakshmanan V; Nayyar N; Bansal D; Sánchez Alvarado A; Vemula PK; Palakodeti D [Ad] Endereço: Institute for Stem Cell Biology and Regenerative Medicine, GKVK campus, Bangalore, Karnataka 560065, India. [Ti] Título: The family of microRNAs is crucial for regeneration of the brain and visual system in the planarian . [So] Source: Development;144(18):3211-3223, 2017 09 15. [Is] ISSN: 1477-9129 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Brain regeneration in planarians is mediated by precise spatiotemporal control of gene expression and is crucial for multiple aspects of neurogenesis. However, the mechanisms underpinning the gene regulation essential for brain regeneration are largely unknown. Here, we investigated the role of the family of microRNAs in planarian brain regeneration. The family ( ) is highly conserved in animals and regulates neurogenesis by facilitating neural differentiation, yet its role in neural wiring and brain organization is not known. We developed a novel method for delivering anti-miRs using liposomes for the functional knockdown of microRNAs. knockdown revealed a key role for these microRNAs in neuronal organization during planarian brain regeneration. Our results also demonstrated an essential role for in the generation of eye progenitors. Additionally, regulates , which encodes an axon guidance protein, either by targeting mRNA or, potentially, by modulating the canonical Notch pathway. Together, our results reveal a role for in regulating the regeneration of a functional brain and visual system. [Mh] Termos MeSH primário: Encéfalo/fisiologia MicroRNAs/metabolismo Planárias/genética Planárias/fisiologia Regeneração Vias Visuais/fisiologia [Mh] Termos MeSH secundário: Animais Fenômenos Biofísicos Gânglios dos Invertebrados/fisiologia Regulação da Expressão Gênica no Desenvolvimento Técnicas de Silenciamento de Genes Lipossomos/química Fusão de Membrana MicroRNAs/genética Modelos Biológicos Neurônios/metabolismo Penetrância Fenótipo Receptores Notch/metabolismo Reprodutibilidade dos Testes Transdução de Sinais Vírus/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T [Nm] Nome de substância: 0 (Liposomes); 0 (MicroRNAs); 0 (Receptors, Notch) [Em] Mês de entrada: 1710 [Cu] Atualização por classe: 171126 [Lr] Data última revisão: 171126 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170816 [St] Status: MEDLINE [do] DOI: 10.1242/dev.144758

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[PMID]: 28707374 [Au] Autor: Uno T; Furutani M; Sakamoto K; Uno Y; Kanamaru K; Mizoguchi A; Hiragaki S; Takeda M [Ad] Endereço: Laboratory of Biological Chemistry, Department of Biofunctional Chemistry, Faculty of Agriculture, Kobe University, Hyogo, Japan. [Ti] Título: Localization and functional analysis of the insect-specific RabX4 in the brain of Bombyx mori. [So] Source: Arch Insect Biochem Physiol;96(1), 2017 Sep. [Is] ISSN: 1520-6327 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Rab proteins are small monomeric GTPases/GTP-binding proteins, which form the largest branch of the Ras superfamily. The different Rab GTPases are localized to the cytosolic face of specific intracellular membranes, where they function as regulators of distinct steps in membrane trafficking. RabX4 is an insect-specific Rab protein that has no close homolog in vertebrates. There is little information about insect-specific Rab proteins. RabX4 was expressed in Escherichia coli and subsequently purified. Antibodies against Bombyx mori RabX4 were produced in rabbits for western immunoblotting and immunohistochemistry. Western blotting of neural tissues revealed a single band, at approximately 26 kD. RabX4-like immunohistochemical reactivity was restricted to neurons of the pars intercerebralis and dorsolateral protocerebrum in the brain. Further immunohistochemical analysis revealed that RabX4 colocalized with Rab6 and bombyxin in the corpus allatum, a neuronal organ that secretes neuropeptides synthesized in the brain into the hemolymph. RabX4 expression in the frontal ganglion, part of the insect stomatogastric nervous system that is found in most insect orders, was restricted to two neurons on the outer region and did not colocalize with allatotropin or Rab6. Furthermore, RNA interference of RabX4 decreased bombyxin expression levels in the brain. These findings suggest that RabX4 is involved in the neurosecretion of a secretory organ in Bombyx mori. [Mh] Termos MeSH primário: Bombyx/metabolismo Corpora Allata/metabolismo Proteínas de Insetos/metabolismo Proteínas rab de Ligação ao GTP/metabolismo [Mh] Termos MeSH secundário: Animais Encéfalo/metabolismo Gânglios dos Invertebrados/metabolismo Hormônios de Inseto/metabolismo Neurônios/metabolismo Neurônios/secreção Neuropeptídeos/metabolismo Neuropeptídeos/secreção Interferência de RNA [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Insect Hormones); 0 (Insect Proteins); 0 (Neuropeptides); 110098-88-9 (bombyxins); 75831-28-6 (allatotropin); EC 3.6.5.2 (rab GTP-Binding Proteins) [Em] Mês de entrada: 1710 [Cu] Atualização por classe: 171003 [Lr] Data última revisão: 171003 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170715 [St] Status: MEDLINE [do] DOI: 10.1002/arch.21404

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[PMID]: 28694209 [Au] Autor: Yu J; Zhang L; Li Y; Li R; Zhang M; Li W; Xie X; Wang S; Hu X; Bao Z [Ad] Endereço: Key Laboratory of Marine Genetics and Breeding, Ocean University of China, Ministry of Education, Qingdao 266003, China. [Ti] Título: Genome-wide identification and expression profiling of the SOX gene family in a bivalve mollusc Patinopecten yessoensis. [So] Source: Gene;627:530-537, 2017 Sep 05. [Is] ISSN: 1879-0038 [Cp] País de publicação: Netherlands [La] Idioma: eng [Ab] Resumo: SOX family is composed of transcription factors that play vital roles in various developmental processes. Comprehensive understanding on evolution of the SOX family requires full characterization of SOX genes in different phyla. Mollusca is the second largest metazoan phylum, but till now, systematic investigation on the SOX family is still lacking in this phylum. In this study, we conducted genome-wide identification of the SOX family in Yesso scallop Patinopecten yessoensis and profiled their tissue distribution and temporal expression patterns in the ovaries and testes during gametogenesis. Seven SOX genes were identified, including SOXB1, B2, C, D, E, F and H, representing the first record in protostomes with SOX members identical to that proposed to exist in the last common ancestor of chordates. Genomic structure analysis identified relatively conserved exon-intron structures, accompanied by intron insertion. Quantitative real-time PCR analysis revealed possible involvement of scallop SOX in various functions, including neuro-sensory cell differentiation, hematopoiesis, myogenesis and gametogenesis. This study represents the first systematic characterization of SOX gene family in Mollusca. It will assist in a better understanding of the evolution and function of SOX family in metazoans. [Mh] Termos MeSH primário: Bivalves/genética Fatores de Transcrição SOX/genética [Mh] Termos MeSH secundário: Animais Bivalves/crescimento & desenvolvimento Éxons Feminino Gametogênese Gânglios dos Invertebrados/metabolismo Regulação da Expressão Gênica no Desenvolvimento Íntrons Masculino Ovário/metabolismo Fatores de Transcrição SOX/metabolismo Testículo/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (SOX Transcription Factors) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170920 [Lr] Data última revisão: 170920 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170712 [St] Status: MEDLINE

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[PMID]: 28413703 [Au] Autor: Swart CC; Wattenberger A; Hackett A; Isaman D [Ad] Endereço: Neuroscience ProgramTrinity CollegeHartfordCTUSA. [Ti] Título: Lifelong neurogenesis in the cerebral ganglion of the Chinese mud snail, . [So] Source: Brain Behav;7(4):e00652, 2017 Apr. [Is] ISSN: 2162-3279 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: INTRODUCTION: A small group of Gastropods possessing giant neurons have long been used to study a wide variety of fundamental neurophysiological phenomena. However, the majority of gastropods do not have large neurons but instead have large numbers of small neurons and remain largely unstudied. We explored neuron size and rate of increase in neuron numbers in the Chinese mud snail, . METHODS: Using histological sections and whole mounts of the cerebral ganglia, we collected cross-sectional data on neuron number and size across the lifespan of this animal. Neurogenesis was verified using Click-it EdU staining. RESULTS: We found that total neuron number in the cerebral ganglia increases throughout the lifespan of this species at a constant rate. New neurons arise primarily near the nerve roots. Females live longer (up to 7 years) than males (up to 5 years) and thus achieve larger numbers of neurons in the cerebral ganglion. Neuron size is consistently small (<10 µm) in the cerebral ganglia at all ages, however, cells in the posterior section of the cerebral ganglia are modestly but significantly larger than cells at the anterior. CONCLUSIONS: These features suggest that and similar species of Caenogastropoda are good candidates for studying gastropod neurogenesis, senescence, and sex differences in the nervous system. [Mh] Termos MeSH primário: Gânglios dos Invertebrados/crescimento & desenvolvimento Gânglios dos Invertebrados/fisiologia Neurogênese/fisiologia Caramujos/crescimento & desenvolvimento Caramujos/fisiologia [Mh] Termos MeSH secundário: Análise de Variância Animais Contagem de Células Tamanho Celular Estudos Transversais Feminino Gânglios dos Invertebrados/citologia Masculino Neurônios/citologia Neurônios/fisiologia Caracteres Sexuais Caramujos/citologia [Pt] Tipo de publicação: JOURNAL ARTICLE [Em] Mês de entrada: 1704 [Cu] Atualização por classe: 170424 [Lr] Data última revisão: 170424 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170418 [St] Status: MEDLINE [do] DOI: 10.1002/brb3.652

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[PMID]: 28315939 [Au] Autor: Zhu L; Selverston AI; Ayers J [Ad] Endereço: Department of Biology, Northeastern University, Boston, MA, 02115, USA. zhu.li@husky.neu.edu. [Ti] Título: The transient potassium outward current has different roles in modulating the pyloric and gastric mill rhythms in the stomatogastric ganglion. [So] Source: J Comp Physiol A Neuroethol Sens Neural Behav Physiol;203(4):275-290, 2017 Apr. [Is] ISSN: 1432-1351 [Cp] País de publicação: Germany [La] Idioma: eng [Ab] Resumo: The crustacean stomatogastric nervous system is a classic model for understanding the effects of modulating ionic currents and synapses at both the cell and network levels. The stomatogastric ganglion in this system contains two distinct central pattern generators: a slow gastric mill network that generates flexible rhythmic outputs (8-20 s) and is often silent, and a fast pyloric network that generates more consistent rhythmic outputs (0.5-2 s) and is always active in vitro. Different ionic conductances contribute to the properties of individual neurons and therefore to the overall dynamics of the pyloric and gastric mill networks. However, the contributions of ionic currents to different dynamics between the pyloric and gastric mill networks are not well understood. The goal of this study is to evaluate how changes in outward potassium current (I ) in the stomatogastric ganglion affect the dynamics of the pyloric and gastric mill rhythms by interfering with normal I activity. We bath-applied the specific I blocker 4-aminopyridine to reduce I 's effect in the stomatogastric ganglion in vitro and evaluated quantitatively the changes in both rhythms. We found that blocking I in the stomatogastric ganglion alters the synchronization between pyloric neurons, and consistently activates the gastric mill rhythm in quiescent preparations. [Mh] Termos MeSH primário: Gânglios dos Invertebrados/citologia Moela não Aviária/fisiologia Neurônios/fisiologia Potássio/metabolismo Piloro/fisiologia [Mh] Termos MeSH secundário: 4-Aminopiridina/farmacologia Potenciais de Ação/efeitos dos fármacos Potenciais de Ação/fisiologia Animais Biofísica Relação Dose-Resposta a Droga Estimulação Elétrica Feminino Análise de Fourier Moela não Aviária/efeitos dos fármacos Masculino Neurônios/efeitos dos fármacos Palinuridae Técnicas de Patch-Clamp Periodicidade Bloqueadores dos Canais de Potássio/farmacologia Piloro/efeitos dos fármacos [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Potassium Channel Blockers); BH3B64OKL9 (4-Aminopyridine); RWP5GA015D (Potassium) [Em] Mês de entrada: 1707 [Cu] Atualização por classe: 171014 [Lr] Data última revisão: 171014 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170320 [St] Status: MEDLINE [do] DOI: 10.1007/s00359-017-1162-z

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[PMID]: 28257837 [Au] Autor: Redeker J; Bläser M; Neupert S; Predel R [Ad] Endereço: Institute for Zoology, Functional Peptidomics Group, University of Cologne, D-50674 Cologne, Zuelpicher Str. 47b, Germany. [Ti] Título: Identification and distribution of products from novel tryptopyrokinin genes in the locust, Locusta migratoria. [So] Source: Biochem Biophys Res Commun;486(1):70-75, 2017 Apr 22. [Is] ISSN: 1090-2104 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: A recent analysis of the genome of Locusta migratoria indicated the presence of four novel insect neuropeptide genes encoding for multiple tryptopyrokinin peptides (tryptoPKs); hitherto only known from pyrokinin or capa genes. In our study, mature products of tryptoPK genes 1 and 2 were identified by mass spectrometry; precursor sequences assigned to the tryptoPK genes 3 and 4 are likely partial sequences of a single precursor. The expression of tryptoPK genes 1 and 2 is restricted to two cells in the subesophageal ganglion, exhibiting not only a unique neuropeptidome but also a very distinctive axonal projection. Comparative neuroendocrinology revealed that homologous cells in other insects also produce tryptoPKs but use other genes to generate this pattern. Since capa and pyrokinin genes are discussed as ancestors of the tryptoPK genes, we completed the hitherto only partially known precursor sequences of these genes by means of transcriptome analyses. The distribution of mature products of CAPA and pyrokinin precursors in the CNS is compared with that of tryptoPKs. In addition, a novel pyrokinin-like precursor is described. [Mh] Termos MeSH primário: Proteínas de Insetos/genética Locusta migratoria/genética Família Multigênica/genética Neuropeptídeos/genética [Mh] Termos MeSH secundário: Sequência de Aminoácidos Animais Sistema Nervoso Central/metabolismo Esôfago/inervação Gânglios dos Invertebrados/citologia Gânglios dos Invertebrados/metabolismo Perfilação da Expressão Gênica/métodos Imuno-Histoquímica Proteínas de Insetos/metabolismo Locusta migratoria/metabolismo Microscopia Confocal Neurônios/metabolismo Neuropeptídeos/metabolismo Isoformas de Proteínas/genética Isoformas de Proteínas/metabolismo Precursores de Proteínas/genética Precursores de Proteínas/metabolismo Proteômica/métodos Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Insect Proteins); 0 (Neuropeptides); 0 (Protein Isoforms); 0 (Protein Precursors); 0 (pyrokinin) [Em] Mês de entrada: 1706 [Cu] Atualização por classe: 170619 [Lr] Data última revisão: 170619 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170305 [St] Status: MEDLINE

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[PMID]: 28119399 [Au] Autor: Zhang Y; Ni W; Horwich AL; Kaczmarek LK [Ad] Endereço: Departments of Pharmacology. [Ti] Título: An ALS-Associated Mutant SOD1 Rapidly Suppresses KCNT1 (Slack) Na -Activated K Channels in Neurons. [So] Source: J Neurosci;37(8):2258-2265, 2017 Feb 22. [Is] ISSN: 1529-2401 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Mutations that alter levels of Slack (KCNT1) Na -activated K current produce devastating effects on neuronal development and neuronal function. We now find that Slack currents are rapidly suppressed by oligomers of mutant human Cu/Zn superoxide dismutase 1 (SOD1), which are associated with motor neuron toxicity in an inherited form of amyotrophic lateral sclerosis (ALS). We recorded from bag cell neurons of , a model system to study neuronal excitability. We found that injection of fluorescent wild-type SOD1 (wt SOD1YFP) or monomeric mutant G85R SOD1YFP had no effect on net ionic currents measured under voltage clamp. In contrast, outward potassium currents were significantly reduced by microinjection of mutant G85R SOD1YFP that had been preincubated at 37°C or of cross-linked dimers of G85R SOD1YFP. Reduction of potassium current was also seen with multimeric G85R SOD1YFP of ∼300 kDa or >300 kDa that had been cross-linked. In current clamp recordings, microinjection of cross-linked 300 kDa increased excitability by depolarizing the resting membrane potential, and decreasing the latency of action potentials triggered by depolarization. The effect of cross-linked 300 kDa on potassium current was reduced by removing Na from the bath solution, or by knocking down levels of Slack using siRNA. It was also prevented by pharmacological inhibition of ASK1 (apoptosis signal-regulating kinase 1) or of c-Jun N-terminal kinase, but not by an inhibitor of p38 mitogen-activated protein kinase. These results suggest that soluble mutant SOD1 oligomers rapidly trigger a kinase pathway that regulates the activity of Na -activated K channels in neurons. Slack Na -activated K channels (KCNT1, K 1.1) regulate neuronal excitability but are also linked to cytoplasmic signaling pathways that control neuronal protein translation. Mutations that alter the amplitude of these currents have devastating effects on neuronal development and function. We find that injection of oligomers of mutant superoxide dismutase 1 (SOD1) into the cytoplasm of invertebrate neurons rapidly suppresses these Na -activated K currents and that this effect is mediated by a MAP kinase cascade, including ASK1 and c-Jun N-terminal kinase. Because amyotrophic lateral sclerosis is a fatal adult-onset neurodegenerative disease produced by mutations in SOD1 that cause the enzyme to form toxic oligomers, our findings suggest that suppression of Slack channels may be an early step in the progression of the disease. [Mh] Termos MeSH primário: Potenciais da Membrana/genética Mutação/genética Proteínas do Tecido Nervoso/metabolismo Neurônios/fisiologia Canais de Potássio/metabolismo Superóxido Dismutase-1/genética [Mh] Termos MeSH secundário: Animais Aplysia/citologia Biofísica Células Cultivadas Estimulação Elétrica Inibidores Enzimáticos/farmacologia Gânglios dos Invertebrados/citologia Seres Humanos Proteínas Luminescentes/genética Proteínas Luminescentes/metabolismo Potenciais da Membrana/efeitos dos fármacos Microinjeções Morfolinos/farmacologia Neurônios/efeitos dos fármacos Técnicas de Patch-Clamp RNA Interferente Pequeno/genética RNA Interferente Pequeno/metabolismo Sódio/farmacologia Superóxido Dismutase-1/química [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Enzyme Inhibitors); 0 (KCNT1 protein, human); 0 (Luminescent Proteins); 0 (Morpholinos); 0 (Nerve Tissue Proteins); 0 (Potassium Channels); 0 (RNA, Small Interfering); 9NEZ333N27 (Sodium); EC 1.15.1.1 (Superoxide Dismutase-1) [Em] Mês de entrada: 1708 [Cu] Atualização por classe: 170822 [Lr] Data última revisão: 170822 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170126 [St] Status: MEDLINE [do] DOI: 10.1523/JNEUROSCI.3102-16.2017

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[PMID]: 28104799 [Au] Autor: Blitz DM; Pritchard AE; Latimer JK; Wakefield AT [Ad] Endereço: Department of Biology, Miami University, Oxford, OH 45056, USA Dawn.Blitz@MiamiOH.edu. [Ti] Título: Muscles innervated by a single motor neuron exhibit divergent synaptic properties on multiple time scales. [So] Source: J Exp Biol;220(Pt 7):1233-1244, 2017 Apr 01. [Is] ISSN: 1477-9145 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Adaptive changes in the output of neural circuits underlying rhythmic behaviors are relayed to muscles via motor neuron activity. Presynaptic and postsynaptic properties of neuromuscular junctions can impact the transformation from motor neuron activity to muscle response. Further, synaptic plasticity occurring on the time scale of inter-spike intervals can differ between multiple muscles innervated by the same motor neuron. In rhythmic behaviors, motor neuron bursts can elicit additional synaptic plasticity. However, it is unknown whether plasticity regulated by the longer time scale of inter-burst intervals also differs between synapses from the same neuron, and whether any such distinctions occur across a physiological activity range. To address these issues, we measured electrical responses in muscles innervated by a chewing circuit neuron, the lateral gastric (LG) motor neuron, in a well-characterized small motor system, the stomatogastric nervous system (STNS) of the Jonah crab, and , sensory, hormonal and modulatory inputs elicit LG bursting consisting of inter-spike intervals of 50-250 ms and inter-burst intervals of 2-24 s. Muscles expressed similar facilitation measured with paired stimuli except at the shortest inter-spike interval. However, distinct decay time constants resulted in differences in temporal summation. In response to bursting activity, augmentation occurred to different extents and saturated at different inter-burst intervals. Further, augmentation interacted with facilitation, resulting in distinct intra-burst facilitation between muscles. Thus, responses of multiple target muscles diverge across a physiological activity range as a result of distinct synaptic properties sensitive to multiple time scales. [Mh] Termos MeSH primário: Braquiúros/fisiologia Neurônios Motores/metabolismo Músculos/inervação Junção Neuromuscular/fisiologia [Mh] Termos MeSH secundário: Animais Braquiúros/citologia Gânglios dos Invertebrados/fisiologia Masculino Contração Muscular Músculos/fisiologia Sinapses/fisiologia [Pt] Tipo de publicação: JOURNAL ARTICLE [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170908 [Lr] Data última revisão: 170908 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170121 [St] Status: MEDLINE [do] DOI: 10.1242/jeb.148908

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[PMID]: 28049417 [Au] Autor: Martin C; Gross V; Pflüger HJ; Stevenson PA; Mayer G [Ad] Endereço: Department of Zoology, University of Kassel, Heinrich-Plett-Str. 40, D-34132, Kassel, Germany. christine.martin@uni-kassel.de. [Ti] Título: Assessing segmental versus non-segmental features in the ventral nervous system of onychophorans (velvet worms). [So] Source: BMC Evol Biol;17(1):3, 2017 Jan 03. [Is] ISSN: 1471-2148 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: BACKGROUND: Due to their phylogenetic position as one of the closest arthropod relatives, studies of the organisation of the nervous system in onychophorans play a key role for understanding the evolution of body segmentation in arthropods. Previous studies revealed that, in contrast to the arthropods, segmentally repeated ganglia are not present within the onychophoran ventral nerve cords, suggesting that segmentation is either reduced or might be incomplete in the onychophoran ventral nervous system. RESULTS: To assess segmental versus non-segmental features in the ventral nervous system of onychophorans, we screened the nerve cords for various markers, including synapsin, serotonin, gamma-aminobutyric acid, RFamide, dopamine, tyramine and octopamine. In addition, we performed retrograde fills of serially repeated commissures and leg nerves to localise the position of neuronal somata supplying those. Our data revealed a mixture of segmental and non-segmental elements within the onychophoran nervous system. CONCLUSIONS: We suggest that the segmental ganglia of arthropods evolved by a gradual condensation of subsets of neurons either in the arthropod or the arthropod-tardigrade lineage. These findings are in line with the hypothesis of gradual evolution of segmentation in panarthropods and thus contradict a loss of ancestral segmentation within the onychophoran lineage. [Mh] Termos MeSH primário: Artrópodes/anatomia & histologia Gânglios dos Invertebrados [Mh] Termos MeSH secundário: Animais Artrópodes/classificação Artrópodes/metabolismo Evolução Biológica Biomarcadores/metabolismo Sistema Nervoso/anatomia & histologia Neurônios Neuropeptídeos Filogenia Serotonina/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Biomarkers); 0 (Neuropeptides); 333DO1RDJY (Serotonin); 34388-59-5 (arginylphenylalaninamide) [Em] Mês de entrada: 1708 [Cu] Atualização por classe: 170809 [Lr] Data última revisão: 170809 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170105 [St] Status: MEDLINE [do] DOI: 10.1186/s12862-016-0853-3

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1			PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
2	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
3	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2

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