Adhesion G protein-coupled receptors (aGPCRs) are expressed in all organs and are involved in various mechanobiological processes. They are heavily alternatively spliced, forecasting an extraordinary molecular structural diversity. Here, we uncovered the existence of unconventional single-transmembrane (1TM)-containing ADGRL/Cirl proteins devoid of the conventional GPCR layout (i.
View Article and Find Full Text PDFScientific advances in environmental data coverage and machine learning algorithms have improved the ability to make large-scale predictions where data are missing. These advances allowed us to develop a spatially resolved proxy for predicting numbers of tropical nearshore marine taxa. A diverse marine environmental spatial database was used to model numbers of taxa from ∼1000 field sites, and the predictions were applied to all 7039 6.
View Article and Find Full Text PDFLearning where to find nutrients while at the same time avoiding toxic food is essential for survival of any animal. Using larvae as a study case, we investigate the role of gustatory sensory neurons expressing IR76b for associative learning of amino acids, the building blocks of proteins. We found surprising complexity in the neuronal underpinnings of sensing amino acids, and a functional division of sensory neurons.
View Article and Find Full Text PDFPredicting reinforcement from sensory cues is beneficial for goal-directed behavior. In insect brains, underlying associations between cues and reinforcement, encoded by dopaminergic neurons, are formed in the mushroom body. We propose a spiking model of the larva mushroom body.
View Article and Find Full Text PDFLarvae of the fruit fly are a powerful study case for understanding the neural circuits underlying behavior. Indeed, the numerical simplicity of the larval brain has permitted the reconstruction of its synaptic connectome, and genetic tools for manipulating single, identified neurons allow neural circuit function to be investigated with relative ease and precision. We focus on one of the most complex neurons in the brain of the larva (of either sex), the GABAergic anterior paired lateral neuron (APL).
View Article and Find Full Text PDFNeuronally orchestrated muscular movement and locomotion are defining faculties of multicellular animals. Due to its simple brain and genetic accessibility, the larva of the fruit fly allows one to study these processes at tractable levels of complexity. However, although the faculty of locomotion clearly pertains to the individual, most studies of locomotion in larvae use measurements aggregated across animals, or animals tested one by one, an extravagance for larger-scale analyses.
View Article and Find Full Text PDFBackground: Janus kinase (JAK) inhibitors have been approved for the treatment of several immune-mediated diseases (IMIDs) including rheumatoid arthritis (RA) and psoriatic arthritis and are in clinical trials for numerous other IMIDs. However, detailed studies investigating the effects of different JAK inhibitors on B cells are missing. Within this study, we therefore aimed to characterize the effect of JAK inhibition on the B cell compartment.
View Article and Find Full Text PDFAnimals, including humans, form oppositely valenced memories for stimuli that predict the occurrence versus the termination of a reward: appetitive 'reward' memory for stimuli associated with the occurrence of a reward and aversive 'frustration' memory for stimuli that are associated with its termination. We characterized these memories in larval Drosophila melanogaster using a combination of Pavlovian conditioning, optogenetic activation of the dopaminergic central-brain DAN-i1864 neuron, and high-resolution video-tracking. This reveals their dependency on the number of training trials and the duration of DAN-i1864 activation, their temporal stability, and the parameters of locomotion that are modulated during memory expression.
View Article and Find Full Text PDFCoral reefs are amongst the most biodiverse ecosystems on earth, but are significantly impacted by agricultural runoff. Despite herbicides being commonly detected in coastal waters, the possibility of herbicide accumulation in coral reef species has largely been overlooked. We investigate the accumulation of several herbicides in five species of coral reef invertebrates collected from ten sites along the Maputaland coast, South Africa.
View Article and Find Full Text PDFAcross the animal kingdom, dopamine plays a crucial role in conferring reinforcement signals that teach animals about the causal structure of the world. In the fruit fly Drosophila melanogaster, dopaminergic reinforcement has largely been studied using genetics, whereas pharmacological approaches have received less attention. Here, we apply the dopamine-synthesis inhibitor 3-Iodo-L-tyrosine (3IY), which causes acute systemic inhibition of dopamine signaling, and investigate its effects on Pavlovian conditioning.
View Article and Find Full Text PDFDopamine serves many functions, and dopamine neurons are correspondingly diverse. We use a combination of optogenetics, behavioral experiments, and high-resolution video-tracking to probe for the functional capacities of two single, identified dopamine neurons in larval Drosophila. The DAN-f1 and the DAN-d1 neuron were recently found to carry aversive teaching signals during Pavlovian olfactory learning.
View Article and Find Full Text PDFAn adaptive transition from exploring the environment in search of vital resources to exploiting these resources once the search was successful is important to all animals. Here we study the neuronal circuitry that allows larval of either sex to negotiate this exploration-exploitation transition. We do so by combining Pavlovian conditioning with high-resolution behavioral tracking, optogenetic manipulation of individually identified neurons, and EM data-based analyses of synaptic organization.
View Article and Find Full Text PDFCommon variable immunodeficiency (CVID) is a disease characterized by increased susceptibility to infections, hypogammaglobulinemia, and immune dysregulation. Although CVID is thought to be a disorder of the peripheral B-cell compartment, in 25% of patients, early B-cell development in the bone marrow is impaired. Because poor B-cell reconstitution after hematopoietic stem cell transplantation has been observed, we hypothesized that in some patients the bone marrow environment is not permissive to B-cell development.
View Article and Find Full Text PDFFinding food is a vital skill and a constant task for any animal, and associative learning of food-predicting cues gives an advantage in this daily struggle. The strength of the associations between cues and food depends on a number of parameters, such as the salience of the cue, the strength of the food reward and the number of joint cue-food experiences. We investigate what impact the strength of an associative odour-sugar memory has on the microbehaviour of Drosophila melanogaster larvae.
View Article and Find Full Text PDFAdjusting behavior to changed environmental contingencies is critical for survival, and reversal learning provides an experimental handle on such cognitive flexibility. Here, we investigate reversal learning in larval Using odor-taste associations, we establish olfactory reversal learning in the appetitive and the aversive domain, using either fructose as a reward or high-concentration sodium chloride as a punishment, respectively. Reversal learning is demonstrated both in differential and in absolute conditioning, in either valence domain.
View Article and Find Full Text PDFCurr Opin Insect Sci
December 2019
Finding and feeding on appropriate food are crucial for all animals. Carbohydrates and amino acids are both essential nutrients, albeit with distinct roles: the former are the main energy source whereas the latter are the building blocks of proteins and are used as neurotransmitters. Despite their crucial role, neither the sensing nor the neuronal processing of amino acids is well understood.
View Article and Find Full Text PDFBackground: Cytotoxic T lymphocyte antigen-4 (CTLA-4) limits T-cell activation and is expressed on T-regulatory cells. Human CTLA-4 deficiency results in severe immune dysregulation. Abatacept (CTLA-4 Ig) is approved for the treatment of rheumatoid arthritis (RA) and its mechanism of action is attributed to effects on T-cells.
View Article and Find Full Text PDFAnimals of many species are capable of "small data" learning, that is, of learning without repetition. Here we introduce larval as a relatively simple study case for such one-trial learning. Using odor-food associative conditioning, we first show that a sugar that is both sweet and nutritious (fructose) and sugars that are only sweet (arabinose) or only nutritious (sorbitol) all support appetitive one-trial learning.
View Article and Find Full Text PDFCoral reefs support rich levels of biodiversity, but are globally threatened by a multitude of factors, including land-sourced pollutants. Concentrations of organochlorine pesticides (OCPs) in three species of coral reef invertebrate at five sites along the Maputaland coast, South Africa were quantified. We aimed to assess spatial and interspecies variations in pesticide accumulation.
View Article and Find Full Text PDFCoral communities are found at high latitude on the East Coast subtropical reefs of South Africa. They are biodiverse, economically important, and afforded World Heritage Site status in the iSimangaliso Wetland Park where some are subjected to recreational use. While the Park's unique coral reefs have, to date, suffered little bleaching from climate change, they are susceptible to the phenomenon and provide a natural laboratory for the study of its effects at high latitude.
View Article and Find Full Text PDFThe role of abiotic parameters in determining the distribution of coral communities was assessed on the relatively pristine Maputaland reefs of South Africa from comprehensive reef survey data. The reefs, on which 42 communities could be defined, occur within three geographically separate complexes. Patterns in benthic distribution could be partially explained by latitude and depth, in particular, with slope, turbulence and reef aspect playing far less role in that order.
View Article and Find Full Text PDFFinding rewards and avoiding punishments are powerful goals of behavior. To maximize reward and minimize punishment, it is beneficial to learn about the stimuli that predict their occurrence, and decades of research have provided insight into the brain processes underlying such associative reinforcement learning. In addition, it is well known in experimental psychology, yet often unacknowledged in neighboring scientific disciplines, that subjects also learn about the stimuli that predict the absence of reinforcement.
View Article and Find Full Text PDFThe brain adaptively integrates present sensory input, past experience, and options for future action. The insect mushroom body exemplifies how a central brain structure brings about such integration. Here we use a combination of systematic single-cell labeling, connectomics, transgenic silencing, and activation experiments to study the mushroom body at single-cell resolution, focusing on the behavioral architecture of its input and output neurons (MBINs and MBONs), and of the mushroom body intrinsic APL neuron.
View Article and Find Full Text PDFBackground: A substantial proportion of refugees, fleeing persecution, torture, and war, are estimated to suffer from psychological traumatization. After being sheltered in reception centers, the refugees come in close contact with different occupational groups, e.g.
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