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How to make and present a poster Ellen M. Carpenter, Ph.D. What is a poster? • An organized visual display of your research project and findings • Posters should be self-explanatory • Posters should be concise Necessary components • • • • • Title/author(s) Abstract Background/significance Data/figures Summary/conclusions Optional components • • • • Methods/approaches Future directions References Acknowledgements (include people who helped and funding sources such as scholarships to you and grants to your mentor) Your Brilliant and Inspiring (but not overly long) Title Authors: You (first), your mentor (last), anyone else you worked with (in the middle) Department and Institution Abstract Data figure Conclusions (bullet points) Figure legend Table title Background Information Background Information/M ethods, etc. XXX Aaa ccc yyy bbb n/a zzz ccc ddd 222 777 kkk Future directions explanation Figure legend Data figure Data figure References Acknowledgements Gene c and Epigene c Factors Contribute to a Possible Mouse Model of Au sm Daniel Hoffmn 1, Brian Mullen2, Ellen Carpenter1,3 1Neuroscience Interdepartmental Program, UCLA, Los Angeles, CA 90095, 2Department of Integra ve Biology and Physiology, UCLA, Los Angeles, CA 90095 3Department of Psychiatry and Biobehavioral Science, UCLA, Los Angeles, CA 90095 Introduction Marble Burying Assay Autistic Spectrum Disorder (ASD) is a group of neurodevelopmental disorders that are defined by deficits in three behavioral categories: social interaction, communication, and repetitive/restricted behaviors. A variety of evidence supports the notion that ASD has a genetic basis, though no single gene can be singled out. One gene, reelin, which encodes the large extracellular matrix protein reelin, has been implicated in ASD in a number of ways. Genome wide linkage studies have shown a connection between ASD and the 7q locus, where reelin is located; in addition, there is evidence of expansion of CGG repeats in the 5’ untranslated region of reelin in some ASD patients. Affected patients also show reduced serum and brain levels of reelin Cerebellum A Epidemiological studies have pointed to an environmental component to ASD as well. One suspected factor is pesticide exposure. In a model proposed by Keller and Persico, prenatal exposure to organophosphates can act in conjunction with existing deficiencies of reelin to contribute to the development of ASD. B C Reeler mice are mice that carry a natural mutation in the reelin gene. They display several locomotor defects, including ataxia, tremors, and a trademark stumbling gait; these defects are due to neuroanatomical changes in the cerebellum and cortex. Reeler heterozygotes show decreased levels of reelin mRNA, reduced reelin protein concentrations, and subtle behavioral deficits, but have no major neuroanatomical defects. In our model, we have used prenatal exposure to chlorpyrifos-oxon (CPO), an organophosphate pesticide, in combination with reeler heterozygote mice (Rl +/-) in an attempt to replicate the neuroanatomical and behavioral defects found in patients with ASD. A D B C D E Reelin Signaling Pathway E Cluster Size Figure 3: (A,B) Before and after photos of the marble-burying arena. 20 marbles were arranged in a 4x5 grid in a fresh cage with approximately 3” of bedding and mice were introduced to the arena for 20 minutes. We counted the number of marbles buried (C), the number of single, isolated marbles (D) and the number and size of marble clusters (E). Reeler heterozygosity, independent of treatment, induced a significant (*, p<.05, ANOVA) increase in the number of marbles buried (C). CPO treatment within the reeler heterozygotes caused a significant (**, p<.01, ANOVA) decrease in the number of single marbles remaining at the end of the testing period (D). Reeler heterozygosity, regardless of treatment, caused an increase in the number of clusters of 4 and 5 marbles over the WT genotypes. Hippocampus Figure 1: Secreted reelin binds to lipoprotein receptors VLDLR and APOER2 on the cell surface, inducing phosphorylation of Dab1, a cytoplasmic adaptor protein. Activated Dab1 clusters and activates SRC family Kinases (SFKs) which further phosphorylate tyrosine residues on Dab1. The phosphorylated Dab1 then goes on, through several signaling pathways, to inhibit phosphorylation of tau, enhancing microtubule and cytoskeleton stability. Reelin also binds to cell surface integrin receptors, which act through Dab1 to stabilize the cytoskeleton. Stabilization of the cytoskeleton works to limit cell motility , allowing secreted reelin to serve as a stop signal to migrating neurons. Generation of a Mouse Model for Autism While no environmental insult has been identified as individually causative for ASD, several have been suggested to act in concert with a genetic predisposition to increase the likelihood of developing ASD. One such insult, identified through epidemiological studies, is organophosphate pesticide exposure. Increased levels of pesticide usage have been linked to increased rates of ASD in the population. Organophosphates specifically inhibit reelin function, as reelin acts as an extracellular serine protease. To elucidate the interaction between environmental and genetic factors in ASD, we exposed pregnant mice to chlorpyrifos-oxon (CPO), the active metabolite of chlorpyrifos, an organophosphate pesticide. We then assessed the of fspring for behavioral and neuroanatomical changes. A B WT Veh WT CPO C D Het Veh Het CPO Figure 5: (A) Low magnification view of a CPO treated reeler heterozygote mouse cerebellum stained for parvalbumin. Boxed regions were selected areas from the central lobe that were analyzed for Purkinje cell density by counting number of labeled Purkinje cells per 100 micron segment. (B-D) High magnification view of boxed regions, starting from the top left and proceeding in a clockwise manner. (E) Histogram of Purkinje cell densities. CPO treatment within the reeler heterozygotes induced a significant decrease in Purkinje cell density (*, p<.05, ANOVA), similar to that seen in ASD patients. Conclusions H E WT Veh WT CPO Het Veh Het CPO WT Veh WT CPO Het Veh Het CPO • Mouse performance in the marble burying assay, which is meant to expose potential repetitive/ restricted behaviors as seen in the ASD, is clearly affected by reeler heterozygosity. This affect can be seen in the traditional measure of total number of marbles buried as well as in our novel analysis of cluster size. • Laminated structures in the CNS known to be affected in ASD patients, including the hippocampus and the cerebellum, both show vulnerability to the loss of a reeler allele, exposure to CPO, or a combination of the two. In both cases, the combination of the two seems to mitigate the phenotype, returning neuroanatomy back towards the WT state. • There is a clear interaction between both environmental and genetic factors on mouse neuroanatomy, which af fects different brain regions in dif ferent ways. • Genetic effects seem to have the greatest influence over mouse behavior within the testing domains, yet the exposure to environmental insult can either exacerbate or reverse the effect of genetic deficit, indicating a complex, yet unpredictable interaction. F G References WT Veh WT Veh Figure 2: Schematic for generating a mouse model for autism. Pregnant female mice heterozygous for the reeler mutation were implanted with an osmotic minipump loaded with either 6 mg/ml CPO or a vehicle control at 13 days of gestation. This is a critical period for cortical neurogenesis, cell migration, and layering of laminated brain structures, making it a good target for investigating the effects of interrupting reelin signaling. 4 dif ferent groups of animals were generated among the of fspring: A) Wild Type Vehicle Exposed B) Wild Type CPO Exposed C) Rl +/- Vehicle Exposed D) Rl +/- CPO Exposed WT CPO Het Veh WT CPO Het Veh Het CPO Het CPO Figure 4: (A-D) Low magnification view of hippocampi in coronal sections of WT Veh (A), WT CPO (B), Het Veh (C), and Het CPO (D) mice brain stained for parvalbumin. Inserts are high magnification view of boxed region. (E-G) Quantification of parvalbumin (PV) positive cells located in the hippocampus. The number of PV positive cells located within the CA1 region (E), CA2 region (F), and CA3 region (G) were counted and compared based on their location either within the pyramidal cell layer or the oriens/alveus (Or/Al). CPO treatment within the reeler heterozygotes caused a significant decrease in the number of PV positive cells within the pyramidal layer of the CA2 and within the pyramidal layer and oriens/alveus of the CA3 (**, p<.05, ANOVA). Reeler heterozygosity on its own induced a significant increase in the number of PV positive cells within the pyramidal layer and oriens/alveus of the CA2 (**, p<.05, ANOVA) and within the pyramidal layer of the CA3 (*, p<.05, ANOVA). (H) Quantification of the PV positive cells within the pyramidal layer of the hippocampus and the oriens/alveus of the hippocampus. The numbers within the two layers are summed to form the total hippocampal cell counts. Reeler heterozygosity in vehicle treated animals induced a significant increase in the number of PV positive cells by all measures (*, p<.05, ANOVA). CPO treatment within reeler heterozygotes induced a significant decrease in the number of PV positive cells by all measures (**, p<.05, ANOVA). Abrahams, B.S., Geschwind, D.H. (2008) Advances in au sm gene cs: on the threshold of a new neurobiology. Nat. Rev. Neurosci. 9: 341-356. Herz, J. and Chen,Y. (2006) Reelin, lipoprotein receptors and synap c plas city. Nat. Rev. Neurosci. 7: 850-859. Keller, F., and Persico, A.M. (2003) The neurobiological context of au sm. Mol. Neurobiol. 28: 1-22. Lawrence, Y.A., Kemper, T.L., Bauman, M.L., Bla , G.J. (2010) Parvalbumin-, calbindin-, and calre ninimmunoreac ve hippocampal interneuron density in au sm. Acta Neurol. Scand. 121: 99-108. Acknowledgements We thank Elvira Khialeeva for her assistance with animal handling, behavioral testing, and her guidance in immunohistological techniques. We thank Jeffrey Chiang for his assistance with statistical analysis of behavioral data. Support for these studies was provided by Autism Speaks and the UCLA Center for Autism Research and Treatment a How to put your poster together • First, ask your mentor, or someone in your lab, if the lab has a particular style or format you should use • If not, use the guidelines on the URC Science website for assistance www.ugresearchsci.ucla.edu/spdinstructions. htm Or use a flash drive. Your abstract • Due Friday, May 6, 2016 by 5 PM. Use the Google submission form on the Neuroscience IDP website: http://www.neurosci.ucla.edu/neuroscienceposter-day.html • Must be written in collaboration with and approved by your mentor BEFORE you turn it in What is an abstract? • A summary of the research to be presented • Abstracts should be about 200-250 words General abstract guidelines • • • • • • Introductory sentence(s) Statement of hypothesis General methods/procedures used Primary result(s) Primary conclusion General statement of the significance of the research Genetic and epigenetic factors contribute to a possible mouse model of autism Daniel Hoffman, Brian Mullen, Elvira Khialeeva, and Ellen M. Carpenter • Autism Spectrum Disorder (ASD) is defined by deficits within three behavioral categories: social interaction, communication, and repetitive/restricted behaviors. While the exact mechanisms of the disorder are unknown, multiple models based on genetic and epigenetic factors have been suggested. One model proposes a combination of reelin deficiency and exposure to organophosphate pesticides. Reelin, an extracellular matrix protein, is responsible for neuronal migration and positioning in laminated structures in the brain. Genome-wide linkage studies show a connection between ASD and the 7q locus, where the reelin gene is located. ASD patients also show reduced levels of reelin protein and mRNA expression. Reelin function may be affected by organophosphate pesticides, which interfere with protein processing, thus exacerbating the effects of reduced reelin expression. We have created a potential ASD animal model using mice heterozygous for the reelin gene that were exposed prenatally to chlorpyrifosoxon, an organophosphate pesticide, at a critical stage in neural development. We then tested several types of behavior in these animals and used histological and immunohistochemical analysis to see changes in the organization of several laminated brain structures. Our findings demonstrate subtle but significant changes in both behavior and brain anatomy and suggest that this mouse model may be useful in studying the underlying causes and possible treatments for ASD. A timeline • Abstracts are due May 6. Give your mentor a draft of your abstract by April 29, so you have a week to revise and rewrite. • Start work on your figures and poster text by May 19. Assemble the figures and go over them with your mentor. • Start assembling your powerpoint file on May 26. This will take several days, particularly to get figures correctly sized and imported. • Print your poster at least one day in advance. • Practice your presentation (aim for 10 minutes). • Hang your poster up on June 2 and enjoy your moment of glory. Your presentation • 10-15 minutes of talking (practice this beforehand) • Be concise and specific • Gauge the knowledge of your audience and tailor your presentation appropriately • Be prepared to answer questions – What is the significance of your research? – What is your contribution to the project? Caveats • Every student must have their own poster and their own project • Don’t make up answers to questions that you don’t know the answer to – saying “I don’t know, but I’d be happy to get back to you with an answer later” is fine • Don’t take credit for someone else’s work Be proud of your work! You have worked hard in a lab, and this is your chance to shine!