Dr. Gaia Tavosanis
Group Leader
German Center for Neurodegenerative Diseases (DZNE)
Carl-Troll-Straße 31
53115 Bonn
gaia.tavosanis(at)dzne.de
+49 (0) 228 / 73 62738
More information
Areas of investigation/research focus
- Fig.1: Genetically labeled subset of visual system interneurons in the lobula plate of an adult Drosophila brain imaged in toto.
Our group is interested in the differentiation and the plasticity of neuronal dendrites. Dendrites represent the input compartment of neurons: they collect information through specific connections that they build with suitable neuronal partners within the nervous system. Thus, the formation of appropriate dendritic arbors is essential for the generation of functional connections within the nervous system and for correct processing of information. Indeed, several human syndromes that lead to mental retardation are accompanied by defective dendrite organization in the central nervous system. Importantly, dendrites remain plastic during adult life and rearrangements of dendrite subdomains accompany plastic process, including adaptation to a changing sensory environment and potentially the formation of long-term memories.
- Fig. 2: A single sensory neuron of the peripheral nervous system of a living Drosophila larva, imaged by confocal microscopy.
Dendrite differentiation
We study the mechanisms underlying the formation of neuronal dendrites in a model organism, Drosophila melanogaster, that offers the possibility of sophisticated genetic manipulations. Currently, we are concentrating on the role of the cellular cytoskeleton in the formation and stabilization of dendritic branches. We combine genetics, time lapse imaging of differentiation in living animals, high-resolution microscopy and molecular analysis to understand how neurons make their sophisticated dendritic processes.
- Fig.3 : Synaptic complexes within the adult mushroom body calyx. These ring-like structures are highlighted with a post-synaptic marker in green. In a small, defined subset of these complexes we also labeled the pre-synaptic compartment in red.
Adult dendrite plasticity
In daily life we are continuously exposed to changes in our environment, including positive or damaging stimuli. How does our nervous system cope with this challenge to achieve adaptation, protection or even a lasting record of given information? The nervous system has the capacity to respond with molecular, functional and structural changes. We analyze the changes that happen at the level of single synaptic complexes within the adult nervous system of the fly upon modifications of the sensory environment. Our long-term goal is to understand the changes that accompany the formation of defined memories and the mechanisms that underlie such changes.
Source of figures 1-3: G. Tavosanis
Figure 2: Reprinted from Dev Biol., Dimitrova S, Reissaus A, Tavosanis G., Slit and Robo regulate dendrite branching and elongation of spacefilling neurons inDrosophila, 18-30., Copyright (2008), with permission from Elsevier
Publications
Dendritic structural plasticity.
G Tavosanis; Dev. Dev Neurobiol. 2012 Jan;72(1):73-86. doi: 10.1002/dneu.20951.
Presynapses in Kenyon Cell Dendrites in the Mushroom Body Calyx of Drosophila.
Christiansen F, Zube C, Andlauer TF, Wichmann C, Fouquet W, Owald D, Mertel S, Leiss F, Tavosanis G, Farca Luna AJ, Fiala A, Sigrist SJ.; J Neurosci. 31 (26): 9696-9707 (2011).
Structural long-term changes at Mushroom Body input synapses
Kremer M.C., Christiansen F., Leiss F., Paehler M., Knapek S., Forstner F., Kloppenburg P., Sigrist S.J. and Tavosanis G.; Current Biology 20 (21):1938-44 (2010).
Synaptic organization of the adult Drosophila mushroom body calyx
Leiss F., Groh C., Butcher N.J., Meinertzhagen I. A. and Tavosanis G.; J Comp. Neurology 517 (6):808-824 (2009).
Comprehensive characterization of dendritic spines in the Drosophila central nervous system
Leiss F., Koper E., Hein I., Fouquet W., Lindner J., Sigrist S. and Tavosanis G.; Dev. Neurobiology 69 (4):221-234 (2009).
Slit and Robo regulate dendrite branching and elongation of space-filling neurons in Drosophila
Dimitrova S., Reissaus A. and Tavosanis G.; Dev. Biol. 324 (1):18-30 (2008).
The Drosophila myosin VI Jaguar controls spindle orientation and basal determinant targeting in mitotic neuroblasts
Petritsch C.*, Tavosanis G.*, Turck C.W., Jan L.Y. & Jan Y.N. (*Equal contribution); Dev. Cell 4: 273-281 (2003).
γ-Tubulin function during female germ-cell development and oogenesis in Drosophila
Tavosanis G.** and Gonzalez C. (**Corresponding author); PNAS 100: 10263-10268 (2003).
Cytological characterization of the mutant phenotypes produced during early embryogenesis by null and hypomorph alleles of the γTub37C gene in Drosophila.
LLamazares S., Tavosanis G. and Gonzalez C.; J. Cell Sc. 112: 659- 667 (1999).
Centrosome and microtubule organization during Drosophila development. (Review)
Gonzalez C., Tavosanis G. and Mollinari C.; J Cell Sc. 111: 2697- 2706 (1998).
Essential role for γ-tubulin in the acentriolar female meiotic spindle of Drosophila
Tavosanis G., LLamazares S., Goulielmos G. and Gonzalez C.; EMBO J. 16: 1809- 1819 (1997).
6DMAP inhibition of early cell cycle events and induction of mitotic abnormalities
Simili M., Pellerano P., Pigullo S., Tavosanis G., Ottaggio L., de Saint-Georges L., Bonatti S.; Mutagenesis 12: 313- 319 (1997).
Cellular targets for the aneugenic action of alkylating agents
Bonatti S., Simili M., Pellerano P., Tavosanis G. and Abbondandolo A.; In “Proceedings on Chromosome segregation and aneuploidy” edited by A. Abbondandolo andB.K. Vig. IST, Genova. Pp.: 265- 273 (1996).
The induction of aneuploidy by alkylated purines: effects on early and late cell cycle events.
Simili M., Pellerano P., Tavosanis G., Arena G., Bonatti S., Abbondandolo A.; Mutagenesis 10: 105- 111 (1995).