2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

Chair: Jan-Peter Hildebrandt
�113 Andreas Vilcinskas M 629 / 14:00
Epigenetic regulation of metamorphosis and immunity in insects
Author: Andreas Vilcinskas 1
Affiliation: 1 Institute of Phytopathology and Applied Zoology, Justus-Liebig-University
of Giessen
Using the greater wax moth Galleria mellonella and the red flour beetle Tribolium
castaneum we explored the epigenetic reprogramming during metamorphosis and
immune responses both at pre- and posttranscriptional level. The transfer of acetyl
groups to histones by enzymes known as histone acetyltransferases (HATs) increases
DNA accessibility and favors transcription, whereas the removal of these groups by
histone deacetylases (HDACs) has the opposite effect. Several HATs and HDACs are
regulated during metamorphosis in G. mellonella and we were able to delay
metamorphosis by inhibiting HATs and accelerate it by inhibiting HDACs. We also
found that the same approach could increase or reduce the survival of insects after
wounding, and identified a number of modulated downstream genes suggesting that
development and responses to wounding and pathogens are coregulated
epigenetically. It therefore appears that the balance between histone acetylation and
deacetylation in insects helps to control transcription during metamorphosis and in
response to wounding and infection.
MicroRNAs are small non-coding RNAs mediating post-transcriptional regulation of
gene expression in eukaryotes. Addressing their role in regulation of physiological
adaptations to environmental stress in insects we selected Tribolium castaneum as a
model. Differential expression of selected immunity and stress-related genes was
quantified using real-time PCR and expression and induction of 455 mature
arthropod miRNAs was determined using proprietary microarrays. We found that
Tribolium exhibits both gender- and stressor-specific adjustment of immune gene
and miRNA expression. Strikingly, we discovered that the number of stressor induced
miRNAs in females is remarkably higher than in males (Freitak et al., 2012: Biology
Letters, in press).
�114 Christine Fink M 629 / 14:15
Microbial communities in the fruit fly's intestine - what we can learn about hostmicrobe
interactions and the outcome of disturbing the homeostatic situation
Authors: Christine Fink 1 , Fabian Staubach 1 , Sven Kuenzel 1 , John Baines 1 , Thomas
Roeder 1
Affiliation: 1 Zoophysiology II, CAU Kiel
The intestinal epithelium of the fruit fly Drosophila melanogaster harbors many
symbiotic microorganisms that are beneficial for the host. The bacterial community
increases lifespan and overall fitness and supports e.g. the degradation of
polysaccharides fatty acids. Disturbing the host microbe-interaction can lead to an
increased incidence for epithelial disruption and the development of chronic
inflammation. To check the role of microbial influence in the fly’s intestine we
invented a model that allow studying the bacterial communities non-invasively. Thus,
193