Nervous System Of Animals Research Articles

The Rotenone Models Reproducing Central and Peripheral Features of Parkinson’s Disease

Parkinson’s disease (PD) is a complex, multi-system, neurodegenerative disorder; PD patients exhibit motor symptoms (such as akinesia/bradykinesia, tremor, rigidity, and postural instability) due to a loss of nigrostriatal dopaminergic neurons, and non-motor symptoms such as hyposmia, autonomic disturbance, depression, and REM sleep behavior disorder (RBD), which precedes motor symptoms. Pathologically, α-synuclein deposition is observed in the central and peripheral nervous system of sporadic PD patients. To clarify the mechanism of neurodegeneration in PD and to develop treatment to slow or stop PD progression, there is a great need for experimental models which reproduce neurological features of PD. Animal models exposed to rotenone, a commonly used pesticide, have received most attention since Greenamyre and his colleagues reported that chronic exposure to rotenone could reproduce the anatomical, neurochemical, behavioral, and neuropathological features of PD. In addition, recent studies demonstrated that rotenone induced neuropathological change not only in the central nervous system but also in the peripheral nervous system in animals. In this article, we review rotenone models especially focused on reproducibility of central and peripheral multiple features of PD. This review also highlights utility of rotenone models for investigation of PD pathogenesis and development of disease-modifying drugs for PD in future.

Shared Cell Biological Functions May Underlie Pleiotropy of Molecular Interactions in the Germ Lines and Nervous Systems of Animals

Evolutionary developmental biology focuses on understanding the origin and evolution of extant biological variation, and the genetic basis for this variation. The genetic toolkit appears largely finite across animals, such that a combination of regulatory evolution, gene recruitment (co-option) and genetic modularity often allow morphological and developmental diversity to arise. Here we summarize a number of observations from across animals, which together suggest that many genes and gene product interaction “modules” originally characterized for their role in the germ line also have neural roles. We explore potential explanations for this observation, noting that in the context of the germ line, these genes appear to have molecular and biochemical properties that make them well-suited to breaking symmetry within cells. The resulting asymmetry is often caused by gene products co-localizing asymmetrically to sub-cellular, non-membrane-bound, electron dense compartments known as ribonucleoprotein (RNP) granules. RNP granules contain high concentrations of translationally quiescent messenger RNAs and proteins and are thought to act as hubs of localized translational control. We propose that the use of strict translational control, which may be achieved molecular processes important for RNP granule formation and/or small RNA-related processes, is an important property of and a commonality between the germ line and nervous tissues, and help explain, at least in part, the close relationship between these two tissue types.

Neural architecture and regeneration in the acoel Hofstenia miamia.

The origin of bilateral symmetry, a major transition in animal evolution, coincided with the evolution of organized nervous systems that show regionalization along major body axes. Studies of Xenacoelomorpha, the likely outgroup lineage to all other animals with bilateral symmetry, can inform the evolutionary history of animal nervous systems. Here, we characterized the neural anatomy of the acoel Hofstenia miamia. Our analysis of transcriptomic data uncovered orthologues of enzymes for all major neurotransmitter synthesis pathways. Expression patterns of these enzymes revealed the presence of a nerve net and an anterior condensation of neural cells. The anterior condensation was layered, containing several cell types with distinct molecular identities organized in spatially distinct territories. Using these anterior cell types and structures as landmarks, we obtained a detailed timeline for regeneration of the H. miamia nervous system, showing that the anterior condensation is restored by eight days after amputation. Our work detailing neural anatomy in H. miamia will enable mechanistic studies of neural cell type diversity and regeneration and provide insight into the evolution of these processes.

KMnO4-mediated reactions for hexachlorophene in aqueous solutions: Direct oxidation, self-coupling, and cross-coupling

Hexachlorophene (HCP) is used in a range of general cleaning and disinfecting products and has received increased attention due to its damaging effect to the central nervous system in animals and its toxicity in humans. The chemical oxidation of HCP by KMnO4 was performed to systematically evaluate the effects of oxidant dose, pH, temperature, typical anions, humic acid (HA), and various matrices on HCP removal. The second-order rate constant for HCP was determined to be 4.83 × 104 M−1 s−1 at pH 7.0 and 25 °C. The presence of HA can inhibit the removal of HCP by KMnO4, while Cl−, NO3−, SO42−, PO43−, and CO32− have negligible effects. Degradation products analysis of the reaction, as well as theoretical calculations of HCP molecule and its phenoxy radical species, indicated that KMnO4 oxidation for HCP included a C–C bridge bond cleavage, hydroxylation, direct oxidation and self-coupling, and cross-coupling reactions. This study revealed that KMnO4 oxidation is an effective technique for eliminating HCP in real water and wastewater.

Structural basis for allosteric transitions of a multidomain pentameric ligand-gated ion channel

Pentameric ligand-gated ion channels (pLGICs) are allosteric receptors that mediate rapid electrochemical signal transduction in the animal nervous system through the opening of an ion pore upon binding of neurotransmitters. Orthologs have been found and characterized in prokaryotes and they display highly similar structure-function relationships to eukaryotic pLGICs; however, they often encode greater architectural diversity involving additional amino-terminal domains (NTDs). Here we report structural, functional, and normal-mode analysis of two conformational states of a multidomain pLGIC, called DeCLIC, from a Desulfofustis deltaproteobacterium, including a periplasmic NTD fused to the conventional ligand-binding domain (LBD). X-ray structure determination revealed an NTD consisting of two jelly-roll domains interacting across each subunit interface. Binding of Ca2+ at the LBD subunit interface was associated with a closed transmembrane pore, with resolved monovalent cations intracellular to the hydrophobic gate. Accordingly, DeCLIC-injected oocytes conducted currents only upon depletion of extracellular Ca2+; these were insensitive to quaternary ammonium block. Furthermore, DeCLIC crystallized in the absence of Ca2+ with a wide-open pore and remodeled periplasmic domains, including increased contacts between the NTD and classic LBD agonist-binding sites. Functional, structural, and dynamical properties of DeCLIC paralleled those of sTeLIC, a pLGIC from another symbiotic prokaryote. Based on these DeCLIC structures, we would reclassify the previous structure of bacterial ELIC (the first high-resolution structure of a pLGIC) as a "locally closed" conformation. Taken together, structures of DeCLIC in multiple conformations illustrate dramatic conformational state transitions and diverse regulatory mechanisms available to ion channels in pLGICs, particularly involving Ca2+ modulation and periplasmic NTDs.

Function and Distribution of the Wamide Neuropeptide Superfamily in Metazoans.

The Wamide neuropeptide superfamily is of interest due to its distinctive functions in regulating life cycle transitions, metamorphic hormone signaling, and several aspects of digestive system function, from gut muscle contraction to satiety and fat storage. Due to variation among researchers in naming conventions, a global view of Wamide signaling in animals in terms of conservation or diversification of function is currently lacking. Here, I summarize the phylogenetic distribution of Wamide neuropeptides based on current data and describe recent findings in the areas of Wamide receptors and biological functions. Common trends that emerge across Cnidarians and protostomes are the presence of multiple Wamide receptors within a single organism, and the fact that Wamide signaling likely functions across an extensive variety of biological systems, including visual, circadian, and reproductive systems. Important areas of focus for future research are the further identification of Wamide-receptor pairs, confirmation of the phylogenetic distribution of Wamides through largescale sequencing and mass spectrometry, and assignment of different functions to specific subsets of Wamide-expressing neurons. More extensive study of Wamide signaling throughout larval development in a greater number of phyla is also important in order to understand the role of Wamides in hormonal regulation. Defining the evolution and function of neuropeptide signaling in animal nervous systems will benefit from an increased understanding of Wamide function and signaling mechanisms in a wider variety of organisms, beyond the traditional model systems.

A Functional Protein Hierarchy Safeguards the Neuronal Transcriptome

The production of alternative RNA variants contributes to the tissue-specific regulation of gene expression. In the animal nervous system, a systematic shift towards distal sites of transcription termination produces transcript signatures that are crucial for neuron development and function. Here, we report that the highly conserved protein ELAV globally regulates all events of neuronal 3’end processing by directly binding to proximal polyadenylation sites of target mRNAs. We uncover an endogenous strategy of functional gene rescue that safeguards neuronal RNA signatures in a loss-of-function context. When not directly repressed by ELAV, the transcript encoding the ELAV paralogue FNE acquires a mini-exon, generating a new protein able to translocate to the nucleus and rescue neuronal 3’end processing. We propose that EXon-Activated functional Rescue is a more widespread mechanism that ensures robustness of processes regulated by a hierarchy, rather than redundancy, of effectors.

S179. ADMINISTRATION OF ROTENONE DURING NEONATAL PERIOD INDUCES SCHIZOPHRENIA-LIKE BEHAVIOR

BackgroundThe neurodevelopment refers to the process that generates and shapes the nervous system of animals. It begins during the earliest stages of embryonic development and it is the last system to be completed after birth, which occurs during the end of adolescence. The majority of mechanisms that constitutes neurodevelopment, such as cell proliferation, migration and neural differentiation, axon growth cone and dendritic filopodia formation as well as synapse are ATP dependents, therefore mitochondria dependents. Hence, disturbs during nervous system development can lead to behavioral deficits and neuropsychiatric disorders, such as schizophrenia. Results of our research group showed that a mitochondria dysfunction during neurodevelopment, by Rotenone (a complex I inhibitor) administration, induces behavioral deficits, such as hyperlocomotion and decreased social interaction, when the rats were young adults (60 days old). Thus, the objective of this study was to evaluate the behavioral deficits in an early age (prodromal phase) and if the behavioral deficits presented at young adulthood could be attenuated or reverted by antipsychotic (Haldol – Hal) or psychostimulant (Metilphenidate – MPD). Notwithstanding, draw a parallel between this animal model and a neuropsychiatric disorder.MethodsTo reach this goal, we treated intraperitoneally wistar puppies (P) with Rotenone 0.1mg/kg (Rot), Saline (Sal) or Vehicle (Veh) (DMSO) during P5-P11. To verify the prodromal phase, we performed behavioral tests (open field, social interaction and contextual fear conditioning) at P35. Therefore, in order to analyze the behavior during the young adulthood (P60), each animal previously treated with Sal, Veh or Rot was then treated intraperitoneally, 30 min before the behavioral tests (open field, social interaction and contextual fear conditioning), with either Saline (Sal-Sal, Veh-Sal, Rot-Sal), Hal (Sal-Hal, Veh-Hal, Rot-Hal) or MPD (Sal-MPD, Veh-MPD, Rot-MPD).ResultsResults showed mean±SEM (n=8 for each group) and analyzed by One-Way Anova and Duncan post-hoc compared to control group (Sal-Sal 100%). At P35, we verified: i) no significant changes in locomotor activity between Rot and Sal; ii) decrease in social interaction after treatment with Rot (68.40%±3.077; p<0.05 in relation to Sal); iii) a reduction in freezing time in contextual fear conditioning task to Rot group (45.20±8.03; p<0.05 when compared to Sal). At P60, we noticed i) an increase in locomotor activity after treatment with Rot-Sal (134.88%±3.95; p<0.05 when compared to Sal-Sal) that was decreased by treatment with Rot-Hal (94.76%±15.74; p<0.05 when compared to Rot-Sal), but not with Rot-MPD (compared to Rot-Sal); ii) a decrease in social interaction at P60 after treatment with Rot-Sal (68.35%±5.87; p<0.05 when compared to Sal-Sal) that was reverted by treatment with Rot-Hal (100.80%±6.66; p<0.05 when compared to Rot-Sal) and also with Rot-MPD (100.6%±6,89; p<0.05 when compared to Rot-Sal); iii) in contextual fear conditioning the animals treated with Rot presented a decrease in freezing response (31.50%±7.36; p<0.05 when compared to Sal-Sal) that was reverted by treatment with Rot-Hal (81.21%±16.65; p<0.05 when compared to Rot-Sal).DiscussionWe concluded that neonatal treatment with Rot promote behavior deficits at young age (P35), such as deficit in social interaction and emotional memory; in young adulthood (P60) we also verified deficit in social interaction and emotional memory, in addition to hyperlocomotion, that are mostly reverted with treatment with Hal, but not with MPD. Altogether our data suggest a relationship between mitochondria inhibition during neurodevelopment leading to schizophrenia-like behavior.

Evolution and diversity of axon guidance Robo receptor family genes

AbstractThe diversity of axon guidance (AG) receptors reflects gains in complexity of the animal nervous system during evolution. Members of the Roundabout (Robo) family of receptors interact with Slit proteins and play important roles in many developmental processes, including AG and neural crest cell migration. There are four members of the Robo gene family. However, the evolutionary history of Robo family genes remain obscure. We analyzed the distribution of Robo family members in metazoan species ranging in complexity from hydras to humans. We undertook a phylogenetic analysis in metazoans, synteny analysis, and ancestral chromosome mapping in vertebrates, and detected selection pressure and functional divergence among four mammalian Robo paralogs. Based on our analysis, we proposed that the ancestral Robo gene could have undergone a tandem duplication in the vertebrate ancestor; then one round of whole genome duplication events occurred before the divergence of ancestral lamprey and gnathostome, generating four paralogs in early vertebrates. Robo4 paralog underwent segmental loss in the following evolutionary process. Our results showed that Robo3 paralog is under more powerful purifying selection pressure compared with other three paralogs, which could correlate with its unique expression pattern and function. Furthermore, we found four sites under positive selection pressure on the Ig1‐2 domains of Robo4 that might interfere with its binding to Slits ligand. Diverge analysis at the amino acid level showed that Robo4 paralog have relatively greater functional diversifications than other Robo paralogs. This coincides with the fact that Robo4 predominantly functions in vascular endothelial cells but not the nervous system.

The toxicity of the technical product, derived triazolinones

Introduction. Technical products that are part of pesticides recommended for use in agriculture must undergo a comprehensive sanitary and Toxicological examination, which is the basis for preventing the adverse effects of pesticides on the health of workers and the population, as well as on the sanitary state of the environment. Purpose of research - the study of the biological effect of the technical product derived triazolinthionov, with its repeated oral intake in mammals (rats), justification of the permissible daily dose (DSD) for humans. Material and methods. Chronic (12 months) experiment was conducted on male rats with a body weight of 200-210 g tested doses: 5.0; 50.0 and 500.0 mg/kg body weight (1 control and 3 experimental groups and 20 individuals each). In the dynamics of the experiment, we observed the condition and behavior of animals, water and food consumption, fixed the timing of death, recorded changes in body weight, physiological, biochemical and hematological parameters. Results. It was found that the dose of 5.0 mg/kg body weight does not cause significant changes in all studied parameters, doses of 50.0 and 500.0 mg/kg body weight had a polytropic effect on the body of experimental animals. Discussion. The studied technical product at repeated intake in doses of 50,0 and 500,0 mg/kg of body weight causes changes in the state of the Central nervous system of animals (statistically significant changes in SPP, total activity, path length, rest time), as well as changes in carbohydrate, lipid, and lipoprotein metabolism in the body, as evidenced by statistically significant changes in biochemical and hematological indicators. Consequently, doses of 50,0 and 500,0 mg/kg of body weight have a polytropic effect on the body of male rats and are effective. The dose of 5.0 mg/kg of body weight, when administered in animals of the experimental group in comparison with animals of the control group, there are no changes in all the studied parameters throughout the experiment, is accepted as invalid. On the basis of an inactive dose of 5.0 mg/kg of body weight and a reserve factor of 100, we have scientifically justified DSD for humans at the level of 0.05 mg/kg. Conclusion. Studies have shown that long-term repeated oral administration of the studied product into the body of animals (male rats) at a dose of 5.0 mg per 1 kg of body weight does not cause statistically significant changes in all the studied parameters, so the indicated dose is invalid. Doses of 50,0 and 500,0 mg/kg MT have a polytropic effect on the body of male rats and are effective. DSD for humans at the level of 0.05 mg/kg is justified based on the inactive dose at the level of 5.0 mg per 1 kg of body weight, established in a 12-month chronic experiment conducted on male rats, and the reserve coefficient of 100 (taking into account the unexpressed specific and long-term effects).

In vitro effect of vanadyl sulfate on cultured primary astrocytes: cell viability and oxidative stress markers.

Exposure to vanadium has been associated with deleterious effects on the central nervous system in animals and humans. Although vanadium-derived pro-oxidant species were reported to be involved in vanadium-mediated neurotoxicity, the ability of this metal to induce oxidative stress markers in glial cells remains to be elucidated. In this study, we investigated the cytotoxicity and the generation of reactive oxygen species (ROS) and nitric oxide (NO) by mouse primary astrocytes after treatment with vanadyl sulfate (VOSO4 ) at concentrations of 20, 50, 100, 200, and 500 μM. The resazurin assay revealed that treatment with VOSO4 for 24 and 48 h at concentrations of 50 and 100 μM, respectively, or higher substantially induced astrocytic cytotoxicity. Intracellular ROS increased after 6-h exposure to the lowest concentration tested (20 μM VOSO4 ) and tended to intensify after 24- and 48-h treatments reaching significant values for 20 and 500 μM VOSO4 . In turn, NO production in the examined cells was elevated after exposure to all concentrations at the 6-, 24-, and 48-h incubation periods. Our study demonstrated the ability of VOSO4 to induce H2 O2 generation in cell-free DMEM/F12 medium. The H2 O2 levels were in the micromolar range (up to 5 μM) and were detected mostly during the first few minutes after VOSO4 addition, suggesting that the generated H2 O2 could not induce toxic effects on the cells. Taken together, these results show VOSO4 induced cytotoxicity in primary astrocyte cells, which may have resulted from vanadyl-stimulated intracellular ROS and NO generation in these cells.

The Effect of Aerobic Physical Activity in Adrenaline Level in White Laboratory Rats.

Introduction:Physical activity is one important factor in the nervous system of animals, it may affect the structure also the function of the brain. Regular aerobic exercises have a good effect on the whole body and thus improves the sense of well-being. Aim:The aim of this experiment was to evaluate the effect of aerobic physical activity in white laboratory rats for 21 days. Methods:The experimental animals used were twenty Wistar rats, divided into 2 groups of 10 animals they were subjected to forced swim test for 21 days for 60-90 min swim. The evaluation of levels of Adrenaline was performed on 1st, 7th, 14th day and on the last day of the experiment day 21 using ELISA kit protocol, also body mass was compared between groups. Results:Our results showed that inducing aerobic physical activity for 21 days on the rats affects their levels of adrenaline. Comparatively, the control group of rats had significantly higher levels of adrenalin compared with day 21 (p=0.435) but lower compared with day 7 and 14 (p=0.231). There was also a difference in body mass which demonstrates adaptability to the surroundings and better coping with physical stress. Conclusion:Regular aerobic activity for 21 days, for 60-90 min swim has a positive impact on adrenaline level also this aerobic exercise protocol could have a positive impact on reducing and maintaining body weight, thus preventing overweight.

The Neuronal Regeneration of Adult Zebrafish After Spinal Cord Injury Is Enhanced by Transplanting Optimized Number of Neural Progenitor Cells

Cell transplantation is commonly used to study the regeneration and repair of the nervous system in animals. However, a technical platform used to evaluate the optimum number of transplanted cells in the recipient’s spinal cord is little reported. Therefore, to develop such platform, we used a zebrafish model, which has transparent embryos, and transgenic line huORFZ, which generates green fluorescent protein (GFP)-expressing cells in the central nervous system under hypoxic stress. After GFP-expressing cells, also termed as hypoxia-responsive recovering cells, were obtained from hypoxia-exposed huORFZ embryos, we transplanted these GFP-(+) cells into the site of spinal cord injury (SCI) in adult wild-type zebrafish, followed by assessing the relationship between number of transplanted cells and the survival rate of recipients. When 100, 300, 500, and 1,000 GFP-(+) donor cells were transplanted into the lesion site of SCI-treated recipients, we found that recipient adult zebrafish transplanted with 300 donor cells had the highest survival rate. Those GFP-(+) donor cells could undergo proliferation and differentiation into neuron in recipients. Furthermore, transplantation of GFP-(+) cells into adult zebrafish treated with SCI was able to enhance the neuronal regeneration of recipients. In contrast, those fish transplanted with over 500 cells showed signs of inflammation around the SCI site, resulting in higher mortality. In this study, we developed a technological platform for transplanting cells into the lesion site of SCI-treated adult zebrafish and defined the optimum number of successfully transplanted cells into recipients, as 300, and those GFP-(+) donor cells could enhance recipient’s spinal cord regeneration. Thus, we provided a practical methodology for studying cell transplantation therapy in neuronal regeneration of zebrafish after SCI.

DNA methylation is maintained with high fidelity in the honey bee germline and exhibits global non-functional fluctuations during somatic development

BackgroundDNA methylation of active genes, also known as gene body methylation, is found in many animal and plant genomes. Despite this, the transcriptional and developmental role of such methylation remains poorly understood. Here, we explore the dynamic range of DNA methylation in honey bee, a model organism for gene body methylation.ResultsOur data show that CG methylation in gene bodies globally fluctuates during honey bee development. However, these changes cause no gene expression alterations. Intriguingly, despite the global alterations, tissue-specific CG methylation patterns of complete genes or exons are rare, implying robust maintenance of genic methylation during development. Additionally, we show that CG methylation maintenance fluctuates in somatic cells, while reaching maximum fidelity in sperm cells. Finally, unlike universally present CG methylation, we discovered non-CG methylation specifically in bee heads that resembles such methylation in mammalian brain tissue.ConclusionsBased on these results, we propose that gene body CG methylation can oscillate during development if it is kept to a level adequate to preserve function. Additionally, our data suggest that heightened non-CG methylation is a conserved regulator of animal nervous systems.

A primal role for the vestibular sense in the development of coordinated locomotion.

Mature locomotion requires that animal nervous systems coordinate distinct groups of muscles. The pressures that guide the development of coordination are not well understood. To understand how and why coordination might emerge, we measured the kinematics of spontaneous vertical locomotion across early development in zebrafish (Danio rerio) . We found that zebrafish used their pectoral fins and bodies synergistically during upwards swims. As larvae developed, they changed the way they coordinated fin and body movements, allowing them to climb with increasingly stable postures. This fin-body synergy was absent in vestibular mutants, suggesting sensed imbalance promotes coordinated movements. Similarly, synergies were systematically altered following cerebellar lesions, identifying a neural substrate regulating fin-body coordination. Together these findings link the vestibular sense to the maturation of coordinated locomotion. Developing zebrafish improve postural stability by changing fin-body coordination. We therefore propose that the development of coordinated locomotion is regulated by vestibular sensation.

Hybrid neuromorphic circuits exploiting non-conventional properties of RRAM for massively parallel local plasticity mechanisms

Recurrent neural networks are currently subject to intensive research efforts to solve temporal computing problems. Neuromorphic processors (NPs), composed of networked neuron and synapse circuit models, natively compute in time and offer an ultralow power solution particularly suited to emerging temporal edge-computing applications (wearable medical devices, for example). The most significant roadblock to addressing useful problems with neuromorphic hardware is the difficulty in maintaining healthy network dynamics in recurrent neural networks. In animal nervous systems, this is achieved via a multitude of adaptive homeostatic mechanisms which act over multiple time scales to counteract network instability induced via drift, component failure, or learning processes such as spike-timing dependent plasticity. One such mechanism is neuronal intrinsic plasticity (IP) where a neuron adapts its parameters which govern its excitability to fire around a target rate. The approach employed in state of the art NPs, based on a central volatile memory remotely setting model parameters, critically constrains parameter variety and bandwidth rendering realization of these essential mechanisms impossible. This paper demonstrates how reconfigurable nonvolatile resistive memories can be incorporated into neuron and synapse circuits allowing memory to be truly colocalized with the computational units in the computing fabric and facilitating the realization of massively parallel local plasticity mechanisms in neuromorphic hardware. Exploiting nonconventional programming operations of HfO2 based RRAM (stochastic SET and the RESET random variable), we propose a technologically plausible IP algorithm and demonstrate its use in the case of a recurrent neural network topology whereby the system self-organizes to sustain stable and healthy network dynamics around a target firing rate.

Exposure to diclofop-methyl induces immunotoxicity and behavioral abnormalities in zebrafish embryos

Diclofop-methyl (DM) is widely used in agriculture and may lead to serious toxicity. However, a limited number of studies have been performed to evaluate the toxicity of DM in the immune and nervous systems of animals. Here, we utilized a good vertebrate model, zebrafish, to evaluate the toxicity of DM during the developmental process. Exposure of zebrafish embryos to 0.1, 0.3 and 0.5 mg/l DM from 6 h post fertilization (hpf) to 72 hpf induced developmental abnormalities, such as shorter body lengths and yolk sac edemas. The number of immune cells in zebrafish larvae was significantly reduced, but the inflammatory response was not influenced by DM treatment. The expression of immune-related genes were downregulated and the levels of oxidative stress were upregulated by DM exposure. Moreover, locomotor behaviors were inhibited by DM exposure. Therefore, our results suggest that DM has the potential to induce immunotoxicity and cause behavioral changes in zebrafish larvae. This study provides new evidence of the influence of DM exposure on aquatic ecosystems.

Categorical colour perception occurs in both signalling and non-signalling colour ranges in a songbird.

Although perception begins when a stimulus is transduced by a sensory neuron, numerous perceptual mechanisms can modify sensory information as it is processed by an animal's nervous system. One such mechanism is categorical perception, in which (1) continuously varying stimuli are labelled as belonging to a discrete number of categories and (2) there is enhanced discrimination between stimuli from different categories as compared with equally different stimuli from within the same category. We have shown previously that female zebra finches ( Taeniopygia guttata) categorically perceive colours along an orange-red continuum that aligns with the carotenoid-based coloration of male beaks, a trait that serves as an assessment signal in female mate choice. Here, we demonstrate that categorical perception occurs along a blue-green continuum as well, suggesting that categorical colour perception may be a general feature of zebra finch vision. Although we identified two categories in both the blue-green and the orange-red ranges, we also found that individuals could better differentiate colours from within the same category in the blue-green as compared with the orange-red range, indicative of less clear categorization in the blue-green range. We discuss reasons why categorical perception may vary across the visible spectrum, including the possibility that such differences are linked to the behavioural or ecological function of different colour ranges.

Artificial intelligence in surgical pathology

Artificial intelligence (AI) is machine intelligence that mimics human cognitive function. It denotes the intelligence presented by some artificial entities including computers and robots. In supervised learning, a machine is trained with data that contain pairs of inputs and outputs. In unsupervised learning, machines are given data inputs that are not explicitly programmed.1 Machine learning refines a model that predicts outputs using sample inputs (features) and a feedback loop. It relies heavily on extracting or selecting salient features, which is a combination of art and science (“feature engineering”). A subset of feature learning is deep learning, which harnesses neural networks modeled after the biological nervous system of animals. Deep learning discovers the features from the raw data provided during training. Hidden layers in the artificial neural network represent increasingly more complex features in the data. Convolutional neural network is a type of deep learning commonly used for image analysis.

Use of Transcriptomic Analysis for the Design of Antibodies to Serve as Neuronal and Synaptic Markers in Macrobrachium crustaceans

Crustaceans are major constituents of aquatic ecosystems and, as such, changes in their behavior and the structure and function of their bodies can serve as indicators of alterations in their immediate environment, such as those associated with climate change and anthropogenic contamination. We want to develop markers of crustacean neural circuits and terminal synaptic structure that can be used for quantifiable characterization with confocal microscopy. When compared with other invertebrate species such as Drosophila and C. elegans, little is known regarding crustacean genomic information, particularly of the animal's nervous system. We have used bioinformatics and a de novo transcriptome assembly approach to identify potential targets for developing specific antibodies to serve as nervous system markers for freshwater prawns of the Macrobrachium spp. These species of prawn are found in rivers of Puerto Rico and are being used to study the impact of exposure to emergent contaminants, such as phthalates and metabolites of pharmaceuticals, in natural sources of freshwater near urban areas.Total RNA was extracted from brain ganglia of Macrobrachium carcinus freshwater prawns and Illumina Next Generation Sequencing was performed using an Eel Pond mRNA Seq Protocol to construct a de novo transcriptome. Transcript sequences related to glutamate receptors were ran through multiple sequence conservation analysis using the MUSCLE webserver. Conserved sequences were analyzed for antigenicity to design specific antibodies. Raw data from the Illumina Sequencing yielded 97,202,662 sequences: 47,630,546 paired and 1,941,570 singletons. Assembly with Trinity resulted in 197,898 assembled sequences, of which 30,576 were annotated: 9,600 annotated by orthology, 17,197 annotated by homology, and 3,779 annotated by transcript families. In the search for glutamate receptor sequences, we found 138 sequences related to ionotropic receptors, 32 sequences related to metabotropic receptors, and 18 sequences to unidentified receptors. Using this information, we were able to develop antibodies for prawn AMPA ionotropic glutamate receptor 1 (GluRIA1), metabotropic glutamate receptor subunit 1 and 4 (mGluRG1S1 and mGluRG3S4), and NMDA ionotropic receptor 2B (GluRNMDA2B). Immunohistochemistry of the ventral nerve cord has thus far shown both punctuate and cell body staining of mGluRG1S1 located throughout all the central nervous system, including the eyestalks, brain, and the circumesophageal, subesophageal, thoracic and abdominal ganglia. The other antibodies are presently being tested in the prawn central nervous system as well as in peripheral synapses such as the neuromuscular junction.Support or Funding InformationNSF DBI‐1337284NSF CREST NSF HRD‐1736019NIH NIMHD 8G12‐MD007600 (RCMI)NIGMS‐RISE R25 GM061838 NSF (USA): CREST HRD‐1137725This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.