Research projects in neuroscience, psychology and biology conducted by current students and recent alumni will be presented at the Robert B. Glassman Memorial Brain, Mind, and Behavior Symposium during Brain Awareness Week on Thursday, November 12 at 5:30 p.m.
Alumni Presenter Abstracts
Time-dependent formation and disappearance of TDP-43 inclusions in a conditional transgenic mouse model of FTLD
Kukreja L1, Kim G1, Sadleir K2, Wang L3, Dong H3, Csernansky J3, Mesulam M-M1, Vassar R2, Geula C1
1Cognitive Neurology and Alzheimer’s Disease Center, Northwestern University, 320 E Superior Street, 11th Floor Searle Building, Chicago, IL 60611, USA.
2 Department of Cell and Molecular Biology, Northwestern University, The Feinberg School of Medicine, 303 E. Chicago Avenue, Chicago, IL 60611 USA.
3 Department of Psychiatry and Behavioral Sciences; Feinberg School of Medicine, ABBOTT 710 N Lake Shore Dr 13th floor, Chicago, IL 60611, USA.
Dementias caused by Frontotemporal lobar degeneration (FTLD) constitute the third most prevalent dementia, after those caused by Alzheimer’s disease and Lewy bodies, and are among the most prevalent dementias of early-onset. The vast majority of these cases contain abnormal precipitates of a phosphorylated and mislocalized form of the Tar DNA/RNA-binding protein-43 (TDP-43). Moreover, overexpressing wild-type or mutant human TDP-43 gene in transgenic animals results in the formation of inclusions and neuronal loss, which have led to the conclusion that TDP-43 pathology leads to FTLD. To directly investigate the temporal sequence of the appearance of TDP-43 inclusions and its relationship to pathology, we employed a conditional transgenic mouse line in which expression of wild-type human TDP-43 is under the control of tetracycline operator sequences. In this study, transgene expression was switched off from birth until weaning age by doxycycline treatment in the mouse diet in order to avoid previously reported complex phenotypes of early neuronal development. In accordance with previous findings, the induction of human TDP-43 recapitulated features of FTLD-TDP, including the formation of phospho-TDP-43 neuronal cytoplasmic inclusions and progressive neurodegeneration. Our immunohistochemical analyses using an antibody that recognizes TDP-43 phosphorylated at Ser-403/404 revealed that inclusions appear as early as 5 days following TDP43 transgene expression. Mice which express the transgene for 10 days show a moderate density of inclusions. The inclusions appear to peak by 14 to 19 days post-transgene expression and decline rapidly thereafter. At these early days of TDP-43 transgene expression, the inclusions are present across frontal, parietal, and temporal cortical areas, and the hippocampus. While inclusions were absent at 8 weeks and 24 weeks of TDP-43 transgene expression, qualitative analysis showed severe neuronal loss in the dentate gyrus. However, the dentate gyrus contained among the lowest densities of inclusions. Thus, the density of TDP-43 inclusions does not directly correlate with neuronal loss in this animal model. It is likely that intracytoplasmic accumulation of TDP-43 oligomers plays a more direct role in neuronal loss and perhaps explains neurodegeneration in the absence of inclusions. Our findings suggest that this TDP-43 mouse model might provide critical information towards understanding how TDP-43 aggregation is linked to neurodegeneration and behavioral deficits in FTLD.
Neuronal signature for crawling and escape swim in Aplysia
E. Moravac, E. S. Hill, A. M. Bruno, M. Humphries, J, Wang, and W. N. Frost
Rosalind Franklin University of Medicine and Science
Studies of neuronal networks need methods for rapidly mapping and characterizing the participating neurons. We recently used VSD imaging paired with computational analyses to characterize network ensembles participating in the Aplysia locomotion motor program (Bruno, Frost and Humphries, Neuron 2015). This study identified several topographically distinct neural ensembles on the dorsal surface of the Aplysia pedal ganglion active during the locomotion motor program. Here we report the topographical locations of neurons that participate in two different behaviors. Also we show the unsupervised consensus clustering that enables us to see statistically related groups of neurons that are related based on their spiking activity. Fifteen minutes VSD recordings were made of neuronal activity during the Pedal nerve 9 elicited locomotion motor program, using a 464 element photodiode array and the fast VSD RH155. Independent component analysis was used to extract single neuron spiking activity from the raw optical data (mean of 120 neurons per preparation). Unsupervised consensus clustering divided the recorded neurons into 8-10 statistically distinct ensembles per preparation, and the position of the neurons comprising each ensemble were mapped on the ganglion surface. These ensembles include both strongly and weakly rhythmic neurons that participated on every cycle, tonic firing neurons, and additional bursting neurons that participated variably in the motor program. This quick survey of the motor program participants on the ganglion’s dorsal surface exemplifies how this approach can be used to rapidly reveal the neural ensembles participating in motor programs of interest. Our results effectively double the number of neurons known to participate in Aplysia locomotion motor program, and demonstrates that the network of interest ( in preparations suitable for the imaging technique) can be mapped, which should facilitate studies of networks in both existing and new preparations.
Adaptive Optics: From Astronomy to Ophthalmology
P. L. Nesper, J. J. Park, S. Khanna, F. Scarinci, and A. A. Fawzi,
Department of Ophthalmology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
Adaptive Optics was originally introduced in the 1950s as a concept to improve astronomical imaging by correcting atmospheric aberration. Today, it is used in major telescopes around the world. Recently, the use of adaptive optics was adapted to compensate for monochromatic aberrations of the eye. Adaptive optics scanning laser ophthalmoscopy has made it possible to visualize and measure the properties of microscopic structures such as photoreceptors in the living human eye. The quantification and structural evaluation of photoreceptors, retinal vasculature and retinal nerve fibers has offered new insights into the pathophysiology of a wide range of retinal diseases, such diabetic retinopathy and age-related macular degeneration. At the forefront of ophthalmic imaged-based therapeutic intervention, adaptive optics provides physicians and scientists with microscopic details that advance the field of ophthalmology.
Wnt 7a Skews Monocyte Differentiation: Relevance to NeuroAIDS
Jennillee Wallace, Lena Al-Harthi
Rush University Medical Center
Monocytes infiltrate the central nervous system for pathological and/or homeostatic purposes and differentiate into proinflammatory M-1, alternative M-2-like macrophages or a variation of intermediate phenotypes. The non-classical CD14+CD16+ monocytes have been observed to more readily traverse the blood brain barrier (BBB), and in HIV infection, an expansion of this phenotype correlates with worsened disease prognosis(1). Increased CD163 expression on brain macrophages/microglia is also associated with HIV encephalitic lesions (2). Published data from our lab illustrates that β-catenin; a protein primarily regulated by a family of morphogenetic glycoproteins known as Wnts, is a restrictive factor for productive HIV infection of monocytes (3). Canonical Wnt signaling stabilizes β-catenin, enabling its translocation to the nucleus, where it is a transcriptional co-activator. Non-canonical Wnts activate the Ca2+ and planar cell polarity (PCP) signaling pathways. We previously demonstrated that β-catenin decreases as monocytes mature, rendering MDMs more susceptible to infection (3). Pertaining to the role of Wnts in the brain, previous studies have reported essential roles of Wnt7a in neurogenesis, neurotransmitter release and synapse formation (5, 6, 7). Our objective is to evaluate the impact of CNS secreted Wnts on monocyte maturation, phenotype and function particularly as it applies to HIV neuropathogenesis. Culturing monocytes for 24 hrs with Wnts 5A, or 7A recombinant human proteins revealed that only Wnt 7A inhibited CD14+CD16- phenotype by 3-, 5- and 7- folds relative to untreated, M-CSF and GM-CSF treated groups, respectively. After 7 days of Wnt 7A treatment, further inhibition of CD14+CD16- (by 10- folds for both untreated and M-CSF treated groups and 25- folds relative to GM-CSF treated group), CD14+CD16+ (3-, 5- and 12- folds for untreated, M-CSF treated and GM-CSF treated groups respectively), as well as CD163 expression (3-, 4-, and 7- folds for untreated, M-CSF and GM-CSF treated groups respectively) was observed. Wnt 7A treatment inhibited secretion of IL1β and DKK1, both factors that have been observed to drive neuroinflammation (8) and neurodegeneration (9), relative to M0, M1 and M2 MDM controls. Finally, immunohistochemical staining for Wnts 1, 3 and 7A in C57BL/6 mouse brain slices revealed robust expression of Wnt 7A in the striatum and hippocampus. Overall, these data suggest that Wnt 7A induces macrophage differentiation, and inhibits inflammation. Ongoing studies are assessing the pathway(s) whether canonical or non-canonical that results in the observed effects, as well as the phenotype and functionality of the Wnt7a influenced MDMs. Ultimately, our studies will provide a better understanding of how Wnts within the CNS skew differentiation and function of infiltrating monocytes.
Student Presenter Abstracts
Ecdysone Regulates Growth in Response to Hypoxia in Drosophila
Y. Zhu, H. Broeker, P. Tank, and A. W. Shingleton
Department of Biology, Lake Forest College, Lake Forest, IL 60045, USA
In almost all animals, hypoxia during development – a deficiency in physiological levels of oxygen – slows growth and reduces final body size. Despite the ubiquity of this phenomenon, however, the developmental mechanisms by which oxygen levels affect growth are largely unknown. In particular, it is unclear whether the response of growth to hypoxia is a result of cell autonomous processes that limit proliferation due to the metabolic constraints imposed by low oxygen, or a regulated process that is controlled systemically. Here we present compelling evidence that the effect of hypoxia on growth rate is regulated systemically in Drosophila. We have previously shown that hypoxia elevates basal levels of ecdysone during the third larval instar. Ecdysone is known to suppress body growth by inhibiting the insulin-signaling pathway. We therefore tested the hypothesis that elevated ecdysone is necessary for growth suppression in hypoxic conditions, by comparing the growth rate of larvae with and without ecdysone in normoxic (21% O2) and hypoxic (10% O2) conditions. We eliminated ecdysone by genetically ablating the prothoracic gland. Consistent with our hypothesis, we found that loss of ecdysone significantly rescued growth rate in hypoxic conditions. These data indicate that the effects of hypoxia on body size can occur as a programmed inhibition of growth, possibly as a means to respond to low oxygen levels in a controlled and coordinated manner.
Quantifying Abdominal Pigmentation in Drosophila
O. S. Ziabari, and A. W. Shingleton
Department of Biology, Lake Forest College, Lake Forest, IL 60045, USA
A major focus of evolutionary-developmental biology is to understand the relationship between genotype and phenotype, and how this relationship evolves. This is most simply achieved through studying a single trait, the developmental regulation of which has been well elucidated. One such trait is the pigmentation pattern on the dorsal abdomen of the female Drosophila melanogaster. Nevertheless, despite extensive research on the developmental mechanisms that control Drosophila pigmentation, the methods used to measure pigmentation and its variation have been largely qualitative rather than quantitative. Here we describe a new approach to quantifying abdominal pigmentation. Our method uses an image of the dorsal abdomen of an adult female fly. Using pixel intensity, we quantify pigmentation along a posterior-anterior transect of each tergite. We can extract multiple aspects of phenotype from these data, such as maximum/minimum pigment intensity and the change in pigmentation across a tergite. This method allows us to rapidly and objectively quantify variation in female pigmentation, both genetic and environmental. We are using this method to study the thermoplasticity of pigmentation and how this plasticity evolves.
Refining the Synthesis of Organometallic Catalysts
A. Tanveer and D. Wiser
Chemistry Department, Lake Forest College, Lake Forest, IL 60045
The structures and energies of bis-amido hafnocenes were computationally analyzed using DFT B3LYP/Lanl2dz in order to predict the composition ratios of the rac and meso isomers. Energy differences between rac and meso isomers predict that 100% rac isomer will be produced with ligands containing tert-butyl bis-Cp and either N-phenyl or N-tert-butyl substituents. The results predict that Jordan’s chelate controlled synthesis will yield 100% or the preferred rac isomer in chelated hafnocenes containing bis-3-tBuCp and PhN(CH2)3NPh or bis-3-tBuCp and tBuN(CH2)3NtBu
The nerve net of the swimming sea anemone Stomphia: How does this animal do so much with so little?
J. Berg 2, C. Brandon 1, T. Norekian 2, and W. N. Frost 1,
1Department of Cell Biology & Anatomy, Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064;
2 Department of Biology, Lake Forest College, Lake Forest, IL 60045
Sea anemones are considered to have the most primitive nervous system, consisting of a diffuse nerve net that disperses throughout their bodies. Despite lacking a brain or central nervous system, Stomphia coccinea stands out from other anemone species, in that they are able to perform complex behaviors in response to certain stimuli. Lake Forest College summer interns Yusuf Ismail and Ryan Porter worked with W. Frost to characterize the behavioral sophistication of Stomphia in 2013. In this study, we expand on their project. One of the most remarkable behaviors that Stomphia exhibit consists of a rapid contraction and escape swim in response to predators. Because this organism can generate such sophisticated behaviors with only a simple nerve net, we decided to further investigate the neurological basis of Stomphia’s nervous system. Specifically, we wanted to explore whether these unique sea anemones had specializations of their nerve net that might account for their complex behaviors. We began by studying the anatomy of their mesenteric tissues, which contain a retractor muscle responsible for Stomphia’s quick contraction of the tentacles, and a parieto-basilar muscle responsible for generating the swim bends. The retractor muscle has a thin layer of epithelial tissue covering the muscle fibers, with a nerve net directly underneath epithelial sheath. In order to obtain the mesenteric tissues, we tried multiple procedures for anaesthetization in order to execute an efficient dissection. We created an anesthetic solution comprised of MgCl2 to sedate the anemones. After sedation, whole mesenteric tissues were dissected and pinned out under a dissection microscope, then prepared for neuronal staining. We used methylene blue solution under a light microscope, while W. Frost and T. Norekian performed α-tubulin antibody fluorescence under a confocal microscope. This allowed us to observe the nerve net associated with the mesenteries. Methylene blue staining revealed linear formations of bipolar neurons running along the muscle fibers of the retractor muscle, which was similar to previous research. However, during the α-tubulin antibody fluorescence, Frost and Norekian were able to stain and observe multiple layers of the mesenteric tissue. The confocal microscopy revealed a dense nerve net between the epithelium sheath and the muscles. The net sent processes to run longitudinally along each muscle fiber. It also revealed a multipolar nerve net located in the mesoglea between the longitudinal and the parieto-basilar muscles. These specialized formations of nerves may lead to enhanced communication between muscular tissues, which could explain the sophisticated behaviors observed in Stomphia. Future research should focus on analyzing physiological measurements of the nerve fibers of living mesenteric tissues. Observations from this could indicate how their neurons fire when the swimming behavior is initiated. Also, more research should be done to further analyze the complex behaviors of this incredible organism.
Strengths and Limitations of a Sexual Assault Prevention Program
N. Bricker, M. Burney, K. Huber, M. Kroeger, and S. M. Long
Psychology Department, Lake Forest College, Lake Forest, IL 60064
The purpose of this study was to evaluate the effectiveness of the up2us program, which aims to educate participants about gender normativity, sexual violence, and positive bystander behavior. This study utilized a sample of undergraduate athletes at a Midwestern community college. Outcomes of the program to be discussed include: endorsement of traditional masculinity, bystander behavior, rape myth acceptance, and readiness to change behavior. Results will be discussed in light of future programming.
Functionality of the Plasma Membrane Citrate Transporter in Liposomes
K. Korth, S. Stark, J. Mayor, and R. Kaplan
Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064; Lake Forest College, Lake Forest, IL 60045
Citrate is a primary metabolite in intermediary metabolism. Via the Kreb’s cycle, it enables cells to generate adenosine triphosphate (ATP), the key form of chemical energy used by eukaryotic cells. A second purpose of citrate, following its breakdown to acetyl CoA and oxaloacetate in the cytoplasm, is to serve as the carbon source fueling fatty acid and cholesterol biosyntheses. There are two sources of cytoplasmic citrate: Thefirst is of mitochondrial origin, generated by the TCA cycle and transported to the cytoplasm by the mitochondrial citrate transporter. The second is of extracellular origin, resulting from food consumption and transported to the cytoplasm by the plasma membrane citrate transporter (PMCT). Past studies regarding the disruption of PMCT function have shown an increased life span in Drosophila and C. elegans. By isolating, purifying, and reconstituting the human PMCT, inhibitors can be developed to prevent or reduce the influx of citrate into human cells. It is hypothesized that the reduction of cytoplasmic citrate in humans can help to alleviate symptoms of obesity, hyperlipidemia, hypercholesterolemia, and Type 2 diabetes. The significant role that citrate contributes to the cell’s energy state makes the PMCT a critical target for research.
Insight in Parkinson’s Disease from Yeasts: Examination of how familial mutants of α-synuclein cause pathology
V.Georgieva, M. N. Marshall, E. Ong, M. Tembo, C. Alvarado, E. Ong, N. Kukulka, S. K. DebBurman
Department of Biology and Neuroscience Program, Lake Forest College, Lake Forest, IL 60045
Parkinson’s disease (PD) is a neurodegenerative disease caused by the death of midbrain dopaminergic neurons. This selective cell death is linked to the misfolding and aggregation of the protein α-synuclein. Familial PD is one of two forms of PD that accounts for 10% cases and is linked to at least seven genes. Six different mutations on α-synuclein itself cause PD. The first three identified familial mutants (A30P, E46K,and A53T) have been well studied in diverse model systems and each mutant generates toxicity in a distinctive way. The more recently discovered familial mutants (H50Q, G51D, and A53E) have just begun to be studied. We created expression system for these three newer mutants in budding and fission yeasts and discovered that each mutant alter α-synuclein’s cellular localization. In addition, H50Q and A53E increase toxicity, while G51D is surprisingly less toxic than wild type α-synuclein. Previously, when we studied the older mutants (A30P, E46K, and A53T) in combination, we found that A30P surprisingly dominated in its phenotype over the other two mutants. Therefore, we asked if any of these three newer mutants was particularly dominant, by describing here the creation of four combinatory mutants H50Q/G51D, H50Q/A53E, G51D/A53E, and H50Q/G51D/A53E, for budding and fission yeast studies. We next plan to evaluate these mutants’ aggregation, localization, and toxicity properties compared to single mutants. These studies will further illuminate the mechanism of pathogenesis linked to each familial PD mutant.
Impact of Phosphodiesterase 10A Inhibition on L-DOPA-Induced Dyskinesias.
C. Tabas1, C. Zoleta2, F. E. Padovan-Neto3, J. F. Harms4, C. J. Schmidt4, and A. R. West3
1Department of Neuroscience, Lake Forest College, Lake Forest, IL 60045; 2Department of Biological Sciences, DePaul University, Chicago, IL 60614; 3Department of Neuroscience, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064; 4Pfizer Global Research and Development, Groton, CT 06340
L-DOPA is currently the most effective treatment for Parkinson’s disease (PD). However, over time chronic L-DOPA treatment loses efficacy and side-effects such as L-DOPA-induced dyskinesias (LIDs) begin to occur. Increasing striatal cyclic nucleotide levels via the administration of phosphodiesterase (PDE) inhibitors has emerged as a new potential pharmacological approach to counteract LIDs. PDEs regulate the diffusion of cAMP/cGMP in striatal medium spiny neurons (MSNs), which are the primary target of dopamine replacement therapies. It has been shown that striatal cAMP/cGMP levels are abnormally low after chronic L-DOPA treatment particularly during the peak of LIDs, suggesting a possible increase in PDE activity. Using TP-10, a PDE10A inhibitor, in the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD, we were able to decrease the expression of LIDs. This gives promise for a different therapeutic target for those with PD, one which could lower LIDs and potentially, the effective dose of L-DOPA used in the clinic. Objective: The current studies assessed the utility of chronic administration (three weeks) of the selective PDE10A inhibitor TP-10 for reversing behavioral correlates of L-DOPA-induced dyskinesias in unilateral 6-OHDA-lesioned rats. Methods: Animals received either a cocktail of: 1) vehicle, 2) L-DOPA (5 mg/kg, i.p.) and benserazide (12.5 mg/kg, i.p.), or 3) L-DOPA/benserazide together with TP-10 (3.2 mg/kg, i.p.). Rats were evaluated by a blinded investigator for LIDs (i.e. dyskinesias) three days per week (Wed-Fri) in a transparent chamber every 30 min and up to 180 min after vehicle/drug administration. The frequency and intensity of LIDs were recorded for individual dyskinetic behaviors and a total combined LIDs score was determined for each rat. Results: The current L-DOPA regimen induced LIDs in the 6-OHDA-lesioned rats. Co-administration with TP-10 significantly attenuated total combined LIDs. Importantly, measures of stepping test were not significantly different across 6-OHDA-lesioned groups treated with L-DOPA alone or L-DOPA plus the PDE10A inhibitor TP-10. Conclusion: These observations demonstrate that robust PDE10A inhibition reduces the incidence and severity of AIMs observed in dyskinetic rats, and indicate that these effects are not simply a result of decreased behavioral activation. Thus, selective targeting of PDE10A signaling in striatal MSNs gives promise for a different therapeutic target for treating LID in patients with PD. Financial Support: The Parkinson’s Disease Foundation; Pfizer, Inc.
The effect of chronic pain on stress-induced analgesia in mice
J. Bortolotti, M. Andrelli, and E. Dimitrov
Biophysics/Physiology Department, Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064; Lake Forest College, Lake Forest, IL 60045
Chronic pain is often a result of multiple diseases such as fibromyalgia, arthritis, and diabetic neuropathy. Chronic pain has been shown to manipulate certain aspects of the pain pathways of the nervous system. When subjected to stress, humans and mice have shown an analgesic effect known as stress-induced analgesia (SIA), through opioid and nonopioid mechanisms. The objective of our study is to determine the effects that chronic pain has on SIA in mice. Information about how such changes can lead to future treatments of diseases that center around chronic pain. In order to study these diseases, 19 Wild Type Mice were used. A baseline pain threshold was established using Von Frey Filaments on each mouse. Next, a baseline tail flick latency (TFL) was determined using Model 33 Tail Flick Analgesia Meter, in which a beam of light was focused on the tail to cause the mice to flick their tail. Each mouse then underwent a Forced Swim Test (FST), consisting of a five-minute swim in room temperature water in a large cylindrical container. Immediately after the FST, TFL was measured again. To induce chronic pain in the mice, 10 of the mice underwent peripheral nerve ligation (PNL) surgery, in which their left sciatic nerve was cuffed using small tubing. The remaining 9 mice were used as a control group. To determine if chronic pain was induced in the 10 mice, pain thresholds were again calculated using Von Frey Filaments 5 and 10 days after surgery. Baseline TFL were measured for both groups on the 10th day and a FST followed by a TFL was administered on the 11th day. Preliminary results show that after the uninjured mice were subjected to a FST followed by a TF, they had an average TFL of 2 seconds greater than just receiving the TF alone. This shows that these mice were experiencing an analgesic effect due to the stressful conditions (FST). After surgery, when subjected to a FST followed by a TF the uninjured mice had an average TFL of 1 second greater than those mice who received surgery, suggesting that the mice that mice with chronic pain due to the surgery showed less of an analgesic effect from the stressful condition (FST). Further tests will be conducted as the research progresses. This includes repeating the baseline TF and then FST followed by the TF on day 30 after the mice have underwent surgery. Due to our preliminary results, we will look to see if the analgesic effect due to the stressful conditions (FST) will decline even further in the mice who are experiencing chronic pain. We may also investigate the effects that an antidepressant has on forced swimming and SIA. Immunostaining for possibly ERK and endocannabinoid CB1 receptors will later be performed to investigate the changes in pain modulation at a neuronal level.
Integration of RFP into elks-1 gene of C. elegans using CRISPR-Cas9 endonuclease
J. Haney and H. Kim
Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064; Lake Forest College, Lake Forest, IL 60045
Advances in genetic engineering have resulted in an increased ability to alter the genome of an organism. One such advance has been the use of endonucleases such as cas9, which comes from the clustered regularly interspaced short palindromic repeats (CRISPR) of the microbial adaptive immune system. The cas9 endonucleases, when introduced together with a site-specific targeting guide RNA (gRNA), have been particularly effective with editing the mammalian genome. The advantage of this method is its specificity, and its ability to introduce any kind of mutations into the genome of an organism. Using cas9 we inserted the coding sequence for the red fluorescent protein (RFP) in frame into the last coding exon of the elks-1 gene, a gene encoding an active zone protein in the presynaptic terminals of C. elegans. A mixture of plasmids was microinjected into the gonads of wild type N2 worms. This plasmid mixture includes plasmids that are designed to express cas9 and elks-1 gRNA, along with a homologous repair construct that has the RFP coding sequence in the middle. The successful insertion of RFP into the elks-1 genomic locus was confirmed first using PCR and then fluorescent microscopy.
The effects of social isolation as a model of autism on neural and behavioral activity as measures for social reward.
H. Heitkotter and J. A. Rosenkranz
Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064; Lake Forest College, Lake Forest, IL 60045
Social isolation in rodents causes deficits in social behavior related to various neurological disorders, such as autism (Koike et al., 2009). Social interaction is a natural reward experimentally measured through conditioned place preference (CPP) (Peartree, et al., 2012). Social reward is related to nucleus accumbens (NAc) activity (Trezza, et al., 2011), and prefrontal cortex (PFC) activity (Van Kerkhof, et al., 2014). Social reward in a model of autism, conveyed through social isolation, is not fully understood. Therefore, we hypothesized that socially isolated rodents would have decreased behavioral and neurological activity related to social reward, indicated by changes in c-fos expression in the NAc and PFC, and changes in behavior related to social interaction. We predict to find decreased c-fos expression in the NAc and PFC, as well as decreased social interaction in social CPP and characteristic behavioral abnormalities associated with social isolation. This study has the potential to increase our understanding of social influence related to neurological disorders.
Alpha-synuclein familial mutant analysis in yeast models
E. Ong, M. Marshall, V. Georgieva, C. Alvarado, M. Tembo, N. Kukulka, M. Munoz, S. K. Debburman
Department of Biology and Neuroscience Program, Lake Forest College, Lake Forest, IL 60045
Parkinson’s disease (PD) is associated with the aggregation and misfolding of alpha-synuclein in midbrain dopaminergic neurons. The gene for alpha-synuclein has six known mutations that directly cause familial forms of PD. The pathological determinants of three mutants (A30P, E46K, and A53T) have been extensively studied and characterized in diverse model systems that indicate that each mutant affects cellular toxicity in distinctive ways. How these three amino acids influence each other’s properties is unclear. Unlike these three mutants, the three more recently discovered familial mutants (H50Q, G51D, and A53E) are not extensively studied. First, we created combination mutants of A30P, E46K, and A53T and characterized them in budding and fission yeast models and found support for the dominance of the A30P mutant over E46K and A53T mutants in both models, shedding new light on the dominance of A30P on alpha-synuclein’s conformation. Secondly, we expressed H50Q, G51D, and A53E mutants in both yeasts models and hypothesized that each would generate toxicity by altering membrane-association, and aggregation properties of alpha-synuclein, but each would do so in distinctive ways. We found that the H50Q and A53E mutants were toxic to yeast, and bound membranes and aggregated within yeast, while G51D was cytoplasmically diffuse and non-toxic. Finally, we are currently characterizing combination mutants of the newer mutants in both yeasts. This work adds insight into the pathogenicity of different familial PD mutants of alpha-synuclein.
Studying the physical cross-links between amino acid side-chains using computational methods
Y. Ismail, and M. Degiacomi
Department of Physical and Theoretical Chemistry, University of Oxford, Oxford, UK; Department of Biology, Lake Forest College, Lake Forest, IL 60045, USA.
Proteins are large and often highly complex macromolecules that consist of one or more amino acid chains. They are responsible for a wide range of functions in living organisms such as catalysing metabolic reactions, transporting molecules, and maintaining the structure of cells. Proteins are sensitive to different environmental conditions and their structure and functions can be altered by such things as heat, pressure, changes in pH, and radiation. One such change involves the formation of physical cross-links between amino acid side-chains or residues. Under certain conditions, residues can chemically bond covalently and in doing so affect the tertiary or quaternary structure of the protein. The formation of cross-links are however dependent on a number of factors such as the distance between residues, the orientation of residues, and the presence of obstructions such as those found on the irregular surface of proteins. Because proteins are not entirely rigid, residues continuously change conformation and hence only certain conformations allow cross-links to form. In order to understand better the effects of cross-links on structure and function of proteins, I wrote a program that would ultimately serve as a tool that considers all possible residue conformations and determines which ones allow the formation of cross-links. By reading Protein Data Bank (.pdb) files that contain structural data in the form of Cartesian coordinates, physical cross-links were rendered in the form of detailed structural images that can be easily studied by researchers.
Insight Into Parkinson’s Disease From Yeasts: Examining the Contributions of a-Synuclein Nitration
Y. Zayats, C. Alvarado, M. N. Marshall, K. Solvang, and S. K. DebBurman.
Department of Biology and Neuroscience Program, Lake Forest College, Lake Forest, IL 60045
Parkinson’s disease (PD) is associated with the aggregation and misfolding of α-synuclein within dying midbrain dopaminergic neurons. α-Synuclein is a 140-amino acid long protein that is further modified by covalent attachments in health and in PD; these modifications include phosphorylation, sumoylation and nitration. α-Synuclein is nitrated at four tyrosine amino acids: Y39, Y125, Y133 and Y136. Cell culture and in vitro studies indicate that α-synuclein nitration increases its aggregation and cellular toxicity, but less is known about nitration effects in organisms. Importantly, we do not know if it is a combination of nitrated amino acids that most contributes to α-synuclein’s aggregation, membrane association, and toxicity. Our lab hypothesized that such a combination will optimally drive cell toxicity and aggregation, and decrease membrane binding. First, we created single mutants on α-synuclein that mimic nitration (Y39C, Y125C, Y133C and Y136C) or block nitration (Y39F, Y125F, Y133F and Y136F) and characterized them in fission and budding yeast models and confirmed that nitration on some residues only mildly affect toxicity, aggregation and α-synuclein localization. In budding yeast, nitration at Y39 influenced membrane localization, and nitration on Y133 had the most impact on toxicity. Fission yeast nitration on Y39 and Y125 affected toxicity the most and nitration on all four tyrosine residues influenced intracellular localization. For my Richter project, I joined a team to create double, triple, and quadruple combination mutants of nitration to study their properties in both yeasts to eventually illuminate the particular combination of nitrotyrosines that is likely key to pathology. Here, we report that all triple/quadruple combination mutants were successfully made for fission yeast. We expect these studies will provide further insight about the influence of nitration on α-synuclein and its role in Parkinson’s disease.
Your Personality Affects How You See Others
K. Meuli, M. Hansen, and N. Wentworth
Richter Scholar Program, Psychology Department, Lake Forest College, Lake Forest, IL 60045
This study considers whether people with different personality traits look at different parts of a social interaction scene. Previous research has found openness to experience to negatively correlate with time spent looking at eyes and positively correlate with time looking all over the image. Extraversion has shown a positive correlation with time spent looking at eyes. In this study, a personality test based on an abbreviated version of the Big Five Personality Test was administered. Then, participants’ gaze was tracked with an ISCAN eye tracker. The hypotheses that people who scored higher in extraversion would spend more time looking at people’s eyes and that people who scored higher in openness to experience would spend more time looking at the entire image were not supported. However, this likely resulted from an overlap in participants who scored highly in the two traits. Subsequent analysis, done by grouping participants into categories based on scores for both traits also had no significance. However, a trend within each group suggested that a relationship between personality as a whole and how people look at images of social interaction might exist.
Developing Retroviral Vectors for the Trans-differentiation of Glia into Neurons
T. Buhr, M. Hoshizaki, and R. Marr
Rosalind Franklin University of Medicine & Science, North Chicago, IL 60064
Repair to the central nervous system is severely limited due to the fact that neurogenesis in the adult brain is nearly nonexistent. However, there is an abundance of support, or glial, cells that continually regenerate throughout life and into old age. It is possible to genetically reprogram these glial cells into neuronal cell types using viral vector-delivered transcription factors. To induce the trans-differentiation of glia into interneurons, we constructed retroviral vectors expressing NKX2.1 and LHX6, which are human transcription factors involved in the formation of interneurons during embryonic development. We used these retroviral vectors containing the transcription factors, NKX2.1 and LHX6, and combined them with retroviral vectors expressing MASH1 and DLX2 to transduce a specific subtype of glial cell, oligodendrocyte progenitor cells (OPC). OPCs are the most highly dividing cell population in the CNS and they replace their numbers if depleted, making them an excellent target cell type for trans-differentiation. By applying a combination of retroviruses containing the transcription factors of interest on rat OPCs, we confirmed differentiation into immature neurons expressing b3-tubulin in vitro.
Effects of repeated concussive traumatic brain injury (TBI) on the hippocampus at acute and chronic time points
S. G. Chiren, N. Jamnia, E. Reisenbigler, R. A. Marr, G. E. Stutzman, D. A. Kozlowski, and D. A. Peterson
DePaul University, Chicago, IL 60614; Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
Traumatic brain injuries (TBI), particularly in milder forms, such as concussions that result from sports or combat, are becoming increasingly common. These mild TBIs are associated with memory deficits. Furthermore, a single TBI increases vulnerability to a subsequent injury. Repeated mild TBIs are now understood to increase likelihood of developing a neurodegenerative disease, such as chronic traumatic encephalopathy, which is commonly found in the brains of injured athletes. However, the precise sequence of degenerative and regenerative responses remains unclear. To model the clinical course of repeated mild TBI, we have utilized a controlled cortical impactor to deliver a closed head injury to male Long-Evans rats. As the hippocampus is central to encoding memory and is known to support adult neurogenesis, we evaluated areas CA1, CA3, and the dorsal and ventral blades of the dentate gyrus. Brains were collected at acute and chronic time points to assess both the initial and long-term responses to impact. Coronal sections through the hippocampus were immunostained to detect mature neurons (NeuN), early neuroblasts (DCX), oligodendrocyte progenitor cells (Olig2 and NG2), astrocytes (GFAP), and sheared axons (β-app). Qualitative trends show neuronal cell loss in area CA1, the dorsal blade of the dentate gyrus, and reduced neuroblasts in the dorsal blade of the dentate gyrus. Additionally, volumetric data showed a decrease in hippocampal volume and an increase in ventricular size. Work in progress using stereological methods (StereoInvestigator software) includes estimation of cell populations (Optical Fractionator) and tissue volume (Cavalieri estimator).
Understanding Parkinson’ Disease in Yeast Models: Interplay between Sumoylation and Phosphorylation of a-Synuclein
R. Thomas, A. N. Roman, G. Lipkin, and S. K. DebBurman
Department of Biology and Neuroscience Program, Lake Forest College, IL 60045
Parkinson’s disease (PD) is a neurodegenerative disorder linked to the loss of dopaminergic neurons in the midbrain. A key pathological marker of PD is the presence of Lewy bodies, which are mainly composed of misfolded a-synuclein protein. α-Synuclein is a highly post-translationally modified protein. While phosphorylation and nitration effects on α-synuclein are well documented, less is known about sumoylation, which is proposed to be neuroprotective based on limited studies. Previous research has shown that the majority of sumoylation takes place on the lysine-96 and lysine-102 sites and increases a-synuclein’s solubility. The effects of phosphorylation are less clear, as published evidence suggests it can be both a protective and pathogenic process in PD. The goal of this project was to test two PD-related properties: 1) sumoylation will protect against α-synuclein toxicity by modifying these PD related properties characteristic of wild-type α-synuclein; 2) lack of sumoylation will be rescued by phosphorylation. First, we have created and expressed sumoylation-blocking variants (K96R, K102R, K96R/K102R) in our well-established budding and fission yeast models through site-directed mutagenesis and yeast transformation. Next, we created phosphorylation blocking (S129A, S87A/S129A) and mimicking (S129D, S87D/S129D) mutations on the sumoylation-deficient a-synuclein background. Using our budding yeast model, we found that reducing α-synuclein sumoylation not only increases its aggregation, but also reduces its association with the plasma membrane. We believe this is the first description of the sumoylation effects on α-synuclein membrane association. Additionally, in budding yeast, when phosphorylation is mimicked on sumoylation-deficient α-synuclein, the aggregation is reduced and membrane binding occurs readily, appearing similar to wild-type form. This suggests that there is an interplay between sumoylation and phosphorylation. In the future, more research will be conducted to further evaluate the connection between sumoylation and other versions of a-synuclein.
Insight Into Parkinson’s Disease From Yeasts: Examining the Contributions of a-Synuclein Nitration
C. Alvarado, M. N. Marshall, Y. Zayats, K. Solvang, and S. K. DebBurman
Department of Biology and Neuroscience Program, Lake Forest College, IL 60045
Parkinson’s disease (PD) is associated with the aggregation and misfolding of α-synuclein within dying midbrain dopaminergic neurons. α-Synuclein is a 140-amino acid long protein that experiences many post-transitional modifications, such as phosphorylation, sumoylation and nitration. The known tyrosine residues available for nitration are Y39, Y125, Y133 and Y136. Cell culture and in vitro studies indicate that α-synuclein nitration increases its aggregation and cellular toxicity, but less is known about the combination of nitration that most contributes to α-synuclein’s aggregation, membrane association, and toxicity in organismal models. We hypothesized that such a combination drives cell toxicity and aggregation, and decrease membrane binding. First, we created single mutants on α-synuclein that mimic nitration (Y39C, Y125C, Y133C and Y136C) or block nitration (Y39F, Y125F, Y133F and Y136F) and characterized them in fission and budding yeast models and confirmed that nitration on some residues only mildly affect toxicity, aggregation and α-synuclein localization. In budding yeast, nitration at Y39 influenced membrane localization, and nitration on Y133 had the most impact on toxicity. Fission yeast nitration on Y39 and Y125 affected toxicity the most and nitration on all four tyrosine residues influenced intracellular localization. We are currently creating double, triple, and quadruple combination mutants of nitration in both yeasts to illuminate that particular combination of multiple tyrosines that is key to pathology. We are also evaluating the effects of our various α-synuclein variants (familial mutants) in two strains that lack enzymes COX5A and COX5B, which increase and decrease overall nitration, respectively, in yeast. We expect these studies will provide further insight about the influence of nitration on α-synuclein and its role in Parkinson’s disease.
Depression and Resilience as Psychological Correlates of Domestic Violence in Urban Syrian Refugee Women
F. Hooda, D. Nahla, and A.H. Mansour
University of Jordan, Amman, Jordan
This cross-sectional, descriptive, pilot study investigated how depression and resilience correlate to domestic violence in urban Syrian refugee women. The study hypothesized that abuse was correlated with high levels of depression and low levels of resilience. A convenience sample of 33 women was surveyed at Al takaful Health Center in Ar-Ramtha, Jordan. Using the Haj-Yahia Abuse Scale (32 items), results showed 57.3% of respondents had faced some form of psychological, physical, sexual, behavioral or economic abuse. Results revealed a particularly high prevalence of psychological abuse. Using the Beck Depression Inventory to assess depression and the Connor-Davidson Resilience Scale to assess resilience, 13 items on the abuse scale were significantly correlated with depression, while 2 items were significantly correlated with resilience. Results supported a significant correlation with depression and a weak correlation with resilience among abused women. The study found evidence of overall high levels of depression and low levels of resilience. Furthermore, 2 in-depth interviews with Syrian refugee women and 1 in-depth interview with the Director of Al takaful Health Center found that there is a lack of support and programs addressing domestic violence and mental health. To best help survivors of domestic violence in host communities, further research is recommended. Additionally, this research urges stakeholders and policy makers to improve upon inefficiencies in psychosocial support, resilience development programs, and upon the challenges that have been identified through this research.
The following six education and outreach exhibits will be led by the students of FIYS106 Medical Mysteries of the Mind course taught by Professor of Biology Dr. Shubhik DebBurman
Medical Mysteries of Sleep
Samuel Curry, Michelle Kielar, Maya Knoska, Tricia Paterakos,
Amanda Penn‐Francis
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present the neuroscience underlying how we sleep and stay awake and they will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.
Medical Mysteries of Language
Alexandra Dunn, Catherine Harding, Isha Khalil, Ayesha Quraishi
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present the neuroscience underlying how we communicate using various forms of communication (verbal, sign, and others) and they will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.
Medical Mysteries of Sexuality
Elizabeth Bacon, Joseph Bove, Brianna Bryson, Daniel Muniz
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present the neuroscience underlying how sex and sexuality and they will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.
Medical Mysteries of Emotions
Maria Bouzarelos Kopta, Olivia Dellomodarme, John Hanna, Abagyle King, Danielle Sychowski
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present the neuroscience underlying how we express emotions and why we do it and will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.
Medical Mysteries of Memory
Austin Conn, Kendra Fobert Victoria Torres
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present the neuroscience underlying how we sleep and stay awake and they will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.
Medical Mysteries of Thought
Michael Buabeng, Yoan Ganev, Simon Kotto, Chisomo, Mwale
First-Year Studies Program and Biology Department, Lake Forest College, Lake Forest, IL 60045
Students of FIYS106 Medical Mysteries of the Mind will present he neuroscience underlying how engage in thought processes and they will delve into several current medical mysteries that are the cutting of scientific research. They will educate the audience using posters, models and interactive activities.