TY  - JOUR
A1  - Kleber, Jörg
A1  - Chen, Yi-Chun
A1  - Michels, Birgit
A1  - Saumweber, Timo
A1  - Schleyer, Michael
A1  - Kähne, Thilo
A1  - Buchner, Erich
A1  - Gerber, Bertram
T1  - Synapsin is required to "boost" memory strength for highly salient events
JF  - Learning and Memory
N2  - Synapsin is an evolutionarily conserved presynaptic phosphoprotein. It is encoded by only one gene in the Drosophila genome and is expressed throughout the nervous system. It regulates the balance between reserve and releasable vesicles, is required to maintain transmission upon heavy demand, and is essential for proper memory function at the behavioral level. Task-relevant sensorimotor functions, however, remain intact in the absence of Synapsin. Using an odor-sugar reward associative learning paradigm in larval Drosophila, we show that memory scores in mutants lacking Synapsin (syn\(^{97}\)) are lower than in wild-type animals only when more salient, higher concentrations of odor or of the sugar reward are used. Furthermore, we show that Synapsin is selectively required for larval short-term memory. Thus, without Synapsin Drosophila larvae can learn and remember, but Synapsin is required to form memories that match in strength to event salience-in particular to a high saliency of odors, of rewards, or the salient recency of an event. We further show that the residual memory scores upon a lack of Synapsin are not further decreased by an additional lack of the Sap47 protein. In combination with mass spectrometry data showing an up-regulated phosphorylation of Synapsin in the larval nervous system upon a lack of Sap47, this is suggestive of a functional interdependence of Synapsin and Sap47.
KW  - mushroom body
KW  - Kenyon cells
KW  - larval drosophila
KW  - Sap47
KW  - phosphorylation
KW  - synaptic vesicles
KW  - short-term memory
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-191440
VL  - 23
IS  - 1
ER  - 
TY  - JOUR
A1  - Niewalda, Thomas
A1  - Völler, Thomas
A1  - Eschbach, Claire
A1  - Ehmer, Julia
A1  - Wen-Chuang, Chou
A1  - Timme, Marc
A1  - Fiala, André
A1  - Gerber, Bertram
T1  - A Combined Perceptual, Physico-Chemical, and Imaging Approach to 'Odour-Distances' Suggests a Categorizing Function of the Drosophila Antennal Lobe
JF  - PLoS One
N2  - How do physico-chemical stimulus features, perception, and physiology relate? Given the multi-layered and parallel architecture of brains, the question specifically is where physiological activity patterns correspond to stimulus features and/or perception. Perceived distances between six odour pairs are defined behaviourally from four independent odour recognition tasks. We find that, in register with the physico-chemical distances of these odours, perceived distances for 3octanol and n-amylacetate are consistently smallest in all four tasks, while the other five odour pairs are about equally distinct. Optical imaging in the antennal lobe, using a calcium sensor transgenically expressed in only first-order sensory or only second-order olfactory projection neurons, reveals that 3-octanol and n-amylacetate are distinctly represented in sensory neurons, but appear merged in projection neurons. These results may suggest that within-antennal lobe processing funnels sensory signals into behaviourally meaningful categories, in register with the physico-chemical relatedness of the odours.
KW  - organization
KW  - cameleon
KW  - honeybee
KW  - map
KW  - neurons
KW  - reveals
KW  - melanogaster
KW  - mushroom body
KW  - spatial representation
KW  - olfactory information
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133510
VL  - 6
IS  - 9
ER  -