A5036329190- Neurobiology and Insect Physiology Research
- Insect and Arachnid Ecology and Behavior
- Olfactory and Sensory Function Studies
- Insect Utilization and Effects
- Physiological and biochemical adaptations
- Animal Behavior and Reproduction
- Invertebrate Immune Response Mechanisms
- Plant and animal studies
- Biochemical Analysis and Sensing Techniques
- Circadian rhythm and melatonin
- Neural dynamics and brain function
- Functional Brain Connectivity Studies
- Photochromic and Fluorescence Chemistry
- Insect and Pesticide Research
- Receptor Mechanisms and Signaling
- Advanced Memory and Neural Computing
- Nicotinic Acetylcholine Receptors Study
- Biomedical and Engineering Education
- Polydiacetylene-based materials and applications
- Ion channel regulation and function
- Molecular Sensors and Ion Detection
- Insect Pheromone Research and Control
- Advanced Chemical Sensor Technologies
- EEG and Brain-Computer Interfaces
University of Lausanne
2010-2020
University of Konstanz
2006-2011
SIB Swiss Institute of Bioinformatics
2011
Freie Universität Berlin
2006-2008
University of Buenos Aires
2003
To sense myriad environmental odors, animals have evolved multiple, large families of divergent olfactory receptors. How and why distinct receptor repertoires their associated circuits are functionally anatomically integrated is essentially unknown. We addressed these questions through comprehensive comparative analysis the Drosophila subsystems that express ionotropic receptors (IRs) odorant (ORs). identify ligands for most IR neuron classes, revealing specificity select amines acids, which...
Ionotropic Receptors (IRs) are a large subfamily of variant ionotropic glutamate receptors present across Protostomia. While these most extensively studied for their roles in chemosensory detection, recent work has implicated two family members, IR21a and IR25a, thermosensation Drosophila. Here we characterize one the evolutionarily deeply conserved receptors, IR93a, show that it is co-expressed functions with IR25a to mediate physiological behavioral responses cool temperatures. IR93a also...
To understand how odor information is represented and processed in the antennal lobe (AL) of Drosophila melanogaster , we have optically recorded glomerular calcium responses to single odors mixtures from olfactory sensory neurons (OSNs) projection (PNs). Odor offer a good tool analyze processing because experimental results can be tested against clear predictions. At level OSNs, representation could predicted response patterns components most cases. PN mixtures, however, provide evidences...
Insects use hygrosensation (humidity sensing) to avoid desiccation and, in vectors such as mosquitoes, locate vertebrate hosts. Sensory neurons activated by either dry or moist air (‘dry cells’ and ‘moist cells’) have been described many insects, but their behavioral roles the molecular basis of hygrosensitivity remain unclear. We recently reported that Drosophila relies on three Ionotropic Receptors (IRs) required for cell function: IR25a, IR93a IR40a (Knecht et al., 2016). Here, we...
Abstract Through analysis of the Drosophila ionotropic receptors (IRs), a family variant glutamate receptors, we reveal that most IRs are expressed in peripheral neuron populations diverse gustatory organs larvae and adults. We characterise IR56d, which defines two anatomically-distinct classes proboscis: one responds to carbonated solutions fatty acids while other represents subset sugar- acid-sensing cells. Mutational indicates together with broadly-expressed co-receptors IR25a IR76b, is...
When an animal smells odor, olfactory sensory neurons generate activity pattern across glomeruli of the first neuropil, insect antennal lobe or vertebrate bulb. Here, several networks local interact with and output neurons--insect projection neurons, mitral/tufted cells. The extent form information processing taking place in these has been subject controversy. To investigate role odor we have used calcium sensor G-CaMP to perform vivo recordings odor-evoked spatiotemporal patterns five...
Undead neurons may underlie the evolution of new olfactory circuits.
Trace conditioning is a form of classical conditioning, where neutral stimulus (conditioned stimulus, CS) associated with following appetitive or aversive (unconditioned US). Unlike delay in trace there stimulus-free gap between CS and US, thus poststimulus neural representation (trace) the required to bridge until its association US. The properties such traces are not well understood, nor their underlying physiological mechanisms. Using behavioral approaches, we studied olfactory honeybees....
Most odors in natural environments are mixtures of several compounds. Perceptually, these can blend into a new "perfume," or some components may dominate as elements the mixture. In order to understand such mixture interactions, it is necessary study events at olfactory periphery, down level single-odorant receptor cells. Does strong ligand present low concentration outweigh effect weak ligands high concentrations? We used fruit fly dOr22a and banana-like odor model system. show that an...
In the present work, we characterized effects of serotonin type 3 receptor ligands on recombinant and native α9α10-containing nicotinic acetylcholine receptors (nAChRs). Our results indicate that α9α10 nAChR shares striking pharmacological properties with 5-HT<sub>3</sub> ligand-gated ion channels. Thus, antagonists block ACh-evoked currents in α9α10-injected <i>Xenopus laevis</i> oocytes a rank order potency tropisetron (IC<sub>50</sub>, 70.1 ± 0.9 nM) > ondansetron 0.6 0.1 μM) = MDL...
The antennal lobe is the primary olfactory center in insect brain and represents anatomical functional equivalent of vertebrate bulb. Olfactory information external world transmitted to by sensory neurons (OSNs), which segregate distinct regions neuropil called glomeruli according specific receptor they express. Here, OSN axons synapse with both local interneurons (LNs), whose processes can innervate many different glomeruli, projection (PNs), convey higher regions. Optical imaging activity...
Abstract Background Odors are represented by specific spatio-temporal activity patterns in the olfactory bulb of vertebrates and its insect analogue, antennal lobe. In honeybees inhibitory circuits AL involved processing odors to shape afferent odor responses. GABA is known as an transmitter lobe, but not all interneurons GABAergic. Therefore we sought analyze functional role histamine for honeybee AL. Results We optically recorded representation before, during after application at input...
Abstract The evolution of animal behaviour is poorly understood. Despite numerous correlations behavioural and nervous system divergence, demonstration the genetic basis interspecific differences remains rare. Here we develop a novel neurogenetic model, Drosophila sechellia , close cousin D. melanogaster that displays profound changes linked to its extreme host fruit specialisation. Through calcium imaging, identify olfactory pathways detecting volatiles. Mutational analysis indicates roles...
ABSTRACT Programmed cell death (PCD) is widespread during neurodevelopment, typically eliminating the surpluses of neuronal production. Employing Drosophila olfactory system, we examined potential cells fated to die contribute circuit evolution. Inhibition PCD sufficient generate many new that express neural markers and exhibit odor-evoked activity. These “undead” neurons a subset receptors that, intriguingly, enriched for recent receptor duplicates include some normally found in other...
Abstract Taste perception is thought to involve the encoding of appetitive and aversive chemical cues in food through a limited number sensory pathways. Through expression analysis complete repertoire Drosophila Ionotropic Receptors (IRs), subfamily ionotropic glutamate receptors, we reveal that majority IRs expressed diverse peripheral neuron populations across gustatory organs both larvae adults, implying numerous roles taste-evoked behaviours. We characterise Ir56d , which labels two...
Abstract Ionotropic Receptors (IRs) are a large subfamily of variant ionotropic glutamate receptors present across Protostomia. While these most extensively studied for their roles in chemosensory detection insects, recent work has implicated two family members, IR21a and IR25a, thermosensation Drosophila . Here we characterize one the deeply conserved receptors, IR93a, show that it is co-expressed functions with IR25a to mediate physiological behavioral responses cool temperatures. IR93a...
The antennal lobe is the primary olfactory center in insect brain and represents anatomical functional equivalent of vertebrate bulb1-5. Olfactory information external world transmitted to by sensory neurons (OSNs), which segregate distinct regions neuropil called glomeruli according specific receptor they express. Here, OSN axons synapse with both local interneurons (LNs), whose processes can innervate many different glomeruli, projection (PNs), convey higher regions. Optical imaging...