Stander Symposium abstract book - University of Dayton

POSTER SESSION 1
Role of retinal determination genes in amyloid beta 42 mediated neurodegeneration in
the Drosophila retina
Presenter(s): Michael T Moran
Advisor(s): Madhuri Kango-Singh, Amit Singh
Biology - Independent Research
Michael T Moran, Meghana Tare, Oorvashi Roy Puli, Madhuri Kango-Singh and Amit SinghOne of the reasons for age related progressive neurodegenerative
disorder, Alzheimer’s disease (AD), is the generation of large aggregates of amyloid beta 42 that are toxic in nature. These amyloid
beta 42 polypeptides which are hydrophobic in nature induce oxidative stress, aberrant signaling and many other cellular alterations that trigger
neuronal cell death. However, the exact mechanisms leading to cell death are not clearly understood. We have developed a Drosophila eye model
of AD where high levels of amyloid beta 42 are expressed in the Drosophila retina which results in induction of cell death. We are testing the role of
core retinal determination (RD) gene machinery in amyloid beta 42 mediated neurodegeneration in the Drosophila eye. The core RD gene machinery
include PAX-6 homolog eyeless (Ey), sine oculis (so), eyes absent (eya) and dacshund (dac). The results from these studies will be presented.
Role of signaling pathways in amyloid-Beta-dependent cell death in Drosophila eye
Presenter(s): Andrew M Steffensmeier
Advisor(s): Madhuri Kango-Singh, Amit Singh
Biology - Honors Thesis
Alzheimer’s disease (AD) is an age-related, progressive neurodegenerative disorder. The reason for Alzheimer’s neuropathology is the generation
of large aggregates of amyloid-Beta 42 that are toxic in nature, and induce oxidative stress, aberrant signaling and many other cellular alterations
that trigger neuronal cell death. However, the exact mechanisms leading to cell death are not clearly understood. We employ a Drosophila eye
model of AD to study how amyloid-Beta 42 causes neurodegeneration. Misexpression of higher levels of amyloid-Beta 42 in the differentiating
photoreceptors of the fly retina rapidly induced aberrant cellular phenotypes and cell death. We found that blocking Caspase-dependent cell
death initially rescued cell death but did not lead to a significant rescue in the adult eye. However, blocking the levels of c-Jun NH (2)-terminal
Kinase (JNK) signaling pathway significantly rescued the neurodegeneration phenotype of amyloid-Beta 42 misexpression both in the eye disc as
well as the adult eye. Here we present our findings on the role of signaling pathways controlling patterning and growth in amyloid plaque mediated
cell death observed in the Drosophila eye.
Scavenging Effects on Carrion Decomposition (SSI: Swine Scene Investigation)
Presenter(s): Alexandra E Calteaux, Lauren E Shewhart
Advisor(s): Mark E Benbow
Biology - Independent Research
The objective of the study was to observe the effects of vertebrate scavenging on aspects of carrion decomposition. Scavenging can influence
the microbial and insect communities on a decomposing body. These communities have forensic applications that enable the determination of
a post mortem interval to estimate the time of death of a corpse. In this study, six swine carcasses were placed on the edge of a forested lot in
Farmersville, Ohio (latitude: 39.66597, longitude: -84.39951) on November 4, 2011. Three carcasses were excluded from scavenging by wire cages,
and three were left uncovered. Motion sensor cameras were mounted near each exposed pig to capture scavenger activity at all times during the
study. To understand how higher or lower temperatures may have been correlated with scavenging events, the average ambient temperature of
days when scavenging occurred were compared to the average ambient temperature of days when no scavenging was observed. The preliminary
data suggest a correlation between temperature and scavenging. As temperature increase, scavenging also increases. The information from this
study can be used to better understand the effect of temperature on the frequency of scavenging events. This in turn can increase the accuracy of
the determination of the post mortem interval.
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