Zur Kurzanzeige

Plasticity of Dopamine-Releasing Central Brain Neurons Underlying Adaptational Feeding-Related Behavior in Drosophila Melanogaster

dc.contributor.advisorFiala, André Prof. Dr.
dc.contributor.authorCoban-Poppinga, Büsra
dc.date.accessioned2020-05-07T12:08:26Z
dc.date.available2020-05-07T12:08:26Z
dc.date.issued2020-05-07
dc.identifier.urihttp://hdl.handle.net/21.11130/00-1735-0000-0005-138E-6
dc.identifier.urihttp://dx.doi.org/10.53846/goediss-7961
dc.language.isoengde
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/
dc.subject.ddc570de
dc.titlePlasticity of Dopamine-Releasing Central Brain Neurons Underlying Adaptational Feeding-Related Behavior in Drosophila Melanogasterde
dc.typedoctoralThesisde
dc.contributor.refereeFiala, André Prof. Dr.
dc.date.examination2020-04-21
dc.description.abstractengAll organisms have to adapt and adjust behaviors to changing environmental conditions. Foraging and feeding behaviors are one of the most adaptive behaviors when changes in nutrient sources occur. Neuronal and behavioral plasticity are not restricted to the developmental phase. An animal must adapt its feeding-related behaviors throughout its life-time to survive. Drosophila melanogaster shows plasticity in adjusting food uptake dependent on the abundance of nutrient resources. It also adapts state-dependent behaviors like food uptake very similarly on mammals. An immense number of studies showed how internal state and state-dependent behaviors are controlled. However, adaptive mechanisms in the underlying neuronal networks dependent on the long term experience of food abundance remain unclear. The involvement of the Drosophila mushroom bodies and related modulatory neurons, e.g. dopaminergic neurons, in experience-dependent behavioral adjustments is well established. Recently, their role in state-dependent foraging behaviors has also been shown. In this study, I addressed the mushroom body extrinsic dopaminergic neurons an element region involved in internal state regulation. Here I show an occurrence questioned the occurrence of structural plasticity in the adult fly brain that depends on the long-term experience of low or high caloric food value as a mechanism for long-lasting adaptation. Parametric changes in the caloric value of the fly food were employed as experimental approach. Fully developed fruit flies were exposed to three different long-term dietaries; hypocaloric, isocaloric, and hypercaloric food. Nutritional decrease in the fly food elucidated enhanced feeding-related behaviors. In addition, a decrease in connectivity was also detected in a certain subset of dopaminergic neurons innervating the mushroom body. These neurons were shown to have reciprocal synapses in this study. Besides, structural refinements were shown to take place in postsynaptic sites. An early activity increase was observed in these dopaminergic neurons upon calorie restriction. Artificially upregulating intrinsic cAMP levels could mimic the structural decrease in connectivity. Therefore, the mechanism behind the decrease in the connectivity under calorie restriction condition are considered to be activity-induced cAMP dependent. Furthermore, this study proved that this artificial mimicking of the structural refinements led to increased feeding behavior similar to the experience hypocaloric food. Finally, the information about the internal state was found to be relayed by a satiety peptide “Allatostatin A”. Disruption of Allatostatin A signaling resulted in a prevention of structural refinements. All in all, this study presents an experience-dependent structural modification accomplished by reciprocal synapses in the adult fly brain. Thereby, this study provides new insights into these types of refinements and shows that modulatory neurons in adult brains remain plastic to give rise to adaptive behavior. This plasticity can be induced by the external factors, i.e. nutrition restriction, and also by artificial mimicking whenever behavioral adjustments are necessary.de
dc.contributor.coRefereeGöpfert, Martin Prof. Dr.
dc.subject.engDrosophila, food uptake, plasticity, long term adaptationde
dc.subject.engmushroom bodyde
dc.identifier.urnurn:nbn:de:gbv:7-21.11130/00-1735-0000-0005-138E-6-8
dc.affiliation.instituteGöttinger Graduiertenschule für Neurowissenschaften, Biophysik und molekulare Biowissenschaften (GGNB)de
dc.subject.gokfullBiologie (PPN619462639)de
dc.identifier.ppn1697712045


Dateien

Thumbnail

Das Dokument erscheint in:

Zur Kurzanzeige