Alzheimer’s in Fruit Flies: Testing a Model System

Justin de Lannoy & Shannon Harringer

Cathy McElwain

Loyola Marymount University, Biology Department

LMU SURP

Alzheimer’s pathology

Fig.1 Structural magnetic resonance imaging (MRI). Image of patient’s brain with severe Alzheimer’s disease (bottom) and age-matched control (top). Atrophy of the hippocampus and cortex can be observed. Adapted from Minati et al. (2009).

Introduction

AB42 plaque

Fig. 3 Neutric plaque comprised of Aβ42 found in hippocampus of Alzheimer’s patient. Adapted from Wang et al. (2000).

Introduction

Alzheimer’s Protein

Fig. 2 The amyloid precursor protein (APP) is processed in two distinct pathways, the α pathway and the β pathway. The β pathway yields 3 products, APP-β, the Aβ42/Aβ40 product and the C-terminal 99 amino acid fragment C99). (after Puglielli, 2002).

Introduction

Alzheimer’s in Drosophila

Introduction

http://marvellousmenagerie.wordpress.com/

Expressing Alzheimer’s proteins in Drosophila melanogaster

Fig. 4 Actin drives the production of the GAL4 which activates the UAS element. This activation causes the expression of the C99 protein.

Introduction

IntroductionIntroduction

Determining Survival RateMethods

Survival Rates – Spring 2011

Fig. 6. A comparison of Finelli et al. with the McElwain Lab. The percent survival was recorded for each day for each line, Aβ42 (Red) and C99 (Blue). The expression of the Aβ42 peptide results in lower survival beginning as early as 10-12 days after emergence. All Aβ42 flies die before day 27. There are still survivors in the C99 line as late as 33 days. This difference is significant (p=.002).

Results

Proposal of Areas to Address

• Changing the promoter

• Mites and bacteria

• Environmental conditions

• Outcross the stocks

Humidity Control

• Previously vials were put in incubator at 29°C without regard of humdity

• Now vials are placed in plastic boxes with papertowels that have absorbed 10mL of water

Summer Survival RatesResults

Spring and Summer Survival RatesResults

Survival Rates – Spring 2011

Fig. 6. A comparison of Finelli et al. with the McElwain Lab. The percent survival was recorded for each day for each line, Aβ42 (Red) and C99 (Blue). The expression of the Aβ42 peptide results in lower survival beginning as early as 10-12 days after emergence. All Aβ42 flies die before day 27. There are still survivors in the C99 line as late as 33 days. This difference is significant (p=.002).

Results

Learning assay

•Conditioning apparatus used to test learning and memory

•Iijima observed statistical learning defects after 6-7days

•Allows for observation Alzheimer’s sooner

Future Directions

• Perfect the behavior assay

• Finish the out-crosses

• Find the right expression of the Alzheimer’s protein to show a good difference in survival

• Test the Moffet peptides

References• Baine M, Georgie D, Shifferraw E, Nguyen T, Nogaj L, Moffet D (2009) Inhibition of a Beta 42 Aggregation

Using Peptides Selected from Combinatorial Libraries. Journal of Peptide Science 15(8): 499-503.

• Finelli A, Kelkar A, Song H, Yang H, Konsolaki Mary (2004) A Model for Studying Alzheimer's a Beta 42-Induced Toxicity in Drosophila Melanogaster. Molecular and Cellular Neuroscience 26(3): 365-75.

• Minati, Ludovico, Trudi Edginton, Maria Grazia Bruzzone, Giorgio Giaccone (2009) Current Concepts in Alzheimer’s Disease: A Multidisciplinary Review. American Journal of Alzheimer’s Disease & Other Dementias. 24(4): 95-121.

• Iijima K, Chiang H-C, Hearn SA, Hakker I, Gatt A, Shenton C, Granger L, Leung A, Iijima-Ando K, Zhong Y (2008) Aβ42 Mutants with Different Aggregation Profiles Induce Distinct Pathologies in Drosphila. PLoS One 3(2): e1703.

• Iijima K, Liu HP, Chiang AS, Hearn SA, Konsolaki M, Zong Y. (2004) Dissecting the pathological effects of human Abeta40 and Abeta42 in Drosophila: a potential model for Alzheimer's disease. Proc Natl Acad Sci U S A. 101(17):6623-6628.

• Iwatsubo T, Odaka A, Suzuki N, Mizusawa H, Nukina N, Ihara Y (1994) Visualization of Aβ 42(43) and Aβ 40 in senile plaques with end-specific Aβ monoclonals: evidence that an initially deposited species is Aβ 42(43). Neuron 13:45–53.

• Tully T, Quinn WG (1985) Classical conditioning and retention in normal and mutant Drosophila melanogastor. J Comp Physiol A. 157(2):263-77.

• Wang, Hoau-Yan, Daniel H.S. Lee, Michael R. D’Andrea, Per A. Peterson, Richard P. Shank, Allen B. Reitz (2000) Β-Amyloid1-42 Binds to α7 Nicotinic Acetylcholine Receptor with High Affinity.The Journal of Biological Chemistry. 275(8): 5626-5632

Acknowledgements

• LMU SURP

• Shelby Chun Fat, Andrew Heslin, Carol Johanson, Anthony Wavrin

• Mary Konsolaki for providing us with the Aβ42 and C99 flies and for her helpful discussions

• The Department of Biology and the College of Science and Engineering for continuing support.

Questions?