@article{PaulsBlechschmidtFrantzmannetal.2018, author = {Pauls, Dennis and Blechschmidt, Christine and Frantzmann, Felix and el Jundi, Basil and Selcho, Mareike}, title = {A comprehensive anatomical map of the peripheral octopaminergic/tyraminergic system of Drosophila melanogaster}, series = {Scientific Reports}, volume = {8}, journal = {Scientific Reports}, number = {15314}, doi = {10.1038/s41598-018-33686-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177412}, year = {2018}, abstract = {The modulation of an animal's behavior through external sensory stimuli, previous experience and its internal state is crucial to survive in a constantly changing environment. In most insects, octopamine (OA) and its precursor tyramine (TA) modulate a variety of physiological processes and behaviors by shifting the organism from a relaxed or dormant condition to a responsive, excited and alerted state. Even though OA/TA neurons of the central brain are described on single cell level in Drosophila melanogaster, the periphery was largely omitted from anatomical studies. Given that OA/TA is involved in behaviors like feeding, flying and locomotion, which highly depend on a variety of peripheral organs, it is necessary to study the peripheral connections of these neurons to get a complete picture of the OA/TA circuitry. We here describe the anatomy of this aminergic system in relation to peripheral tissues of the entire fly. OA/TA neurons arborize onto skeletal muscles all over the body and innervate reproductive organs, the heart, the corpora allata, and sensory organs in the antennae, legs, wings and halteres underlining their relevance in modulating complex behaviors.}, language = {en} } @article{NguyenBeetzMerlinetal.2022, author = {Nguyen, Tu Anh Thi and Beetz, M. Jerome and Merlin, Christine and Pfeiffer, Keram and el Jundi, Basil}, title = {Weighting of celestial and terrestrial cues in the monarch butterfly central complex}, series = {Frontiers in Neural Circuits}, volume = {16}, journal = {Frontiers in Neural Circuits}, issn = {1662-5110}, doi = {10.3389/fncir.2022.862279}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-279445}, year = {2022}, abstract = {Monarch butterflies rely on external cues for orientation during their annual long-distance migration from Northern US and Canada to Central Mexico. These external cues can be celestial cues, such as the sun or polarized light, which are processed in a brain region termed the central complex (CX). Previous research typically focused on how individual simulated celestial cues are encoded in the butterfly's CX. However, in nature, the butterflies perceive several celestial cues at the same time and need to integrate them to effectively use the compound of all cues for orientation. In addition, a recent behavioral study revealed that monarch butterflies can rely on terrestrial cues, such as the panoramic skyline, for orientation and use them in combination with the sun to maintain a directed flight course. How the CX encodes a combination of celestial and terrestrial cues and how they are weighted in the butterfly's CX is still unknown. Here, we examined how input neurons of the CX, termed TL neurons, combine celestial and terrestrial information. While recording intracellularly from the neurons, we presented a sun stimulus and polarized light to the butterflies as well as a simulated sun and a panoramic scene simultaneously. Our results show that celestial cues are integrated linearly in these cells, while the combination of the sun and a panoramic skyline did not always follow a linear integration of action potential rates. Interestingly, while the sun and polarized light were invariantly weighted between individual neurons, the sun stimulus and panoramic skyline were dynamically weighted when both stimuli were simultaneously presented. Taken together, this dynamic weighting between celestial and terrestrial cues may allow the butterflies to flexibly set their cue preference during navigation.}, language = {en} } @article{HabensteinAminiGruebeletal.2020, author = {Habenstein, Jens and Amini, Emad and Gr{\"u}bel, Kornelia and el Jundi, Basil and R{\"o}ssler, Wolfgang}, title = {The brain of Cataglyphis ants: Neuronal organization and visual projections}, series = {Journal of Comparative Neurology}, volume = {528}, journal = {Journal of Comparative Neurology}, number = {18}, doi = {10.1002/cne.24934}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218212}, pages = {3479 -- 3506}, year = {2020}, abstract = {Cataglyphis ants are known for their outstanding navigational abilities. They return to their inconspicuous nest after far-reaching foraging trips using path integration, and whenever available, learn and memorize visual features of panoramic sceneries. To achieve this, the ants combine directional visual information from celestial cues and panoramic scenes with distance information from an intrinsic odometer. The largely vision-based navigation in Cataglyphis requires sophisticated neuronal networks to process the broad repertoire of visual stimuli. Although Cataglyphis ants have been subjected to many neuroethological studies, little is known about the general neuronal organization of their central brain and the visual pathways beyond major circuits. Here, we provide a comprehensive, three-dimensional neuronal map of synapse-rich neuropils in the brain of Cataglyphis nodus including major connecting fiber systems. In addition, we examined neuronal tracts underlying the processing of visual information in more detail. This study revealed a total of 33 brain neuropils and 30 neuronal fiber tracts including six distinct tracts between the optic lobes and the cerebrum. We also discuss the importance of comparative studies on insect brain architecture for a profound understanding of neuronal networks and their function.}, language = {en} }