BIOMEDICAL SCIENCES GRADUATE PROGRAM SUMMER 2014

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1 THE OHIO STATE UNIVERSITY BIOMEDICAL SCIENCES GRADUATE PROGRAM SUMMER 2014 Elizabeth Stofko Barrie PhD Candidate Genetic Factors Regulating Expression of Dopaminergic Genes July 15 th, DHLRI 1:00 PM

2 VITA May, Born Amherst, NY January, B.S. Biology, Case Western Reserve University June 2008-present Graduate Research Associate, The Ohio State University COMMITTEE MEMBERS Wolfgang Sadee, Dr. rer. nat. R. Thomas Boyd, Ph.D. Howard Gu, Ph.D. Amanda Toland, Ph.D.

3 ABSTRACT Genetic differences are one of the main contributors to diversity in clinical phenotypes. This project identifies and defines genetic factors affecting dopamine dysregulation focusing on three genes in dopamine signaling: DBH, COMT and SNCA. To study this I measure allelic expression, selecting RNA samples from postmortem human tissue that are heterozygous for a marker SNP, and quantitate the expression of each allele. Dopamine beta hydroxylase (DBH) encodes an enzyme which converts dopamine to norepinephrine and plays a role in multiple disorders. A promoter SNP, rs has been associated with low DBH and high dopamine plasma levels; however, underlying mechanisms remain uncertain. I found a tissue-specific effect of rs in liver, with up to 11 fold differences in allelic and overall mrna expression (p< to 2x10-7 and p< respectively), indicating decreased transcription. Interestingly, locus coeruleus and adrenal gland, the main sources of DBH in the body, did not demonstrate this robust effect; only small AEI ratios were detected in these tissues. More frequent than rs and in linkage disequilibrium with it, a second SNP, rs was associated with reduced allelic mrna expression in all tissues tested. This dual mechanism accounts for the previously described genotype effect on DBH plasma levels, with a novel role for liver as an important source of variability in DBH levels. In combination, rs and rs contribute to strongly reduced mrna expression in the liver, reducing transcription in a tissue selective manner. In mice, Dbh mrna levels in the liver correlated with cardiovascular risk phenotypes. Using a PheWAS (phenome-wide association study) analysis, the minor alleles of rs and rs were associated with sympathetic phenotypes including angina pectoris. Testing combined effects of rs and rs indicated robust protection against myocardial infarction in three clinical cohorts. These results demonstrate profound effects of common DBH variants on expression in sympathetically innervated organs, modulating clinical phenotypes

4 responsive to peripheral sympathetic tone. In a pathway parallel to DBH, catechol-o-methyltransferase (COMT) converts dopamine to an inactive metabolite. Measuring allelic expression, I found almost half of the African-American samples tested demonstrate a significant mrna fold change, while only one Caucasian sample demonstrates AEI, indicating the presence of a regulatory variant which is frequent only in this population and has not yet been described. Extensive sequencing of regions predicted to harbor this regulatory variant, up to 500 kb from the gene, did not reveal a variant associated with these instances of AEI. It is clear there is a factor, acting predominantly in African-Americans, regulating allelic expression and I have ruled out hundreds of SNPs as being the cause. Alpha-synuclein (SNCA) is involved in dopamine regulation, and implicated in degeneration of dopaminergic neurons. Allelic mrna analysis indicates the presence of a regulatory variant. I have found an association with rs , likely affecting, or marking differential 3 UTR usage. This approach has revealed the presence of frequent regulatory variants in all three genes studied. Functional SNPs contributing to dysregulation of dopamine can be tested for association with clinical phenotypes using large publicly available genome-wide association datasets.

5 RECENT ABSTRACTS AND PRESENTATIONS 1. Regulatory polymorphisms in DBH affect peripheral gene expression and associate with MI, Pharmacogenomics Research Meeting, Orlando, FL, April, 2014, Oral presentation. 2. Genetic variants in dopamine beta-hydroxylase decrease gene expression and serve as biomarkers for cardiovascular disease, Hayes Graduate Research Forum, Columbus, OH, February, 2014, Oral presentation. 3. Regulatory polymorphisms in the gene encoding dopamine beta-hydroxylase (DBH) affect transcription, Gordon Research Conference, Catecholamines, West Dover, VT, August, 2013, Poster. 4. Dopamine beta-hydroxylase polymorphisms regulate allelic and total mrna expression in liver, 11 th Annual OSUWMC Research Day, Columbus, OH, April, 2012, Poster. 5. Next-generation sequencing assesses alternate transcription and allelic expression imbalance in neurocognitive disorders, The Ohio State University Medical Center Research Day, Columbus, OH, April 2011, Poster. 6. Development of a novel strain of non-obese diabetic (NOD) mice with targeted disruption of the CD103 gene, The Ohio State University s Department of Surgery Research Conference, Columbus, OH, May 2010, Oral presentation. 7. Development of a novel strain of non-obese diabetic (NOD) mice with targeted disruption of the CD103 gene, Midwest Islet Conference, Indianapolis, IN, May 2010, Poster. 8. Innate immune recognition of Fusobacterium nucleatum is mediated via TLR2 and TLR4, Keystone Symposia on Innate Immunity: Signaling Mechanisms, Keystone, CO, February 2008, Poster.

6 RECENT PUBLICATIONS 1. Barrie ES, Weinshenker D, Pendergrass S, Lange L, Ritchie M, Wilson J, Kuivaniemi H, Tromp G, Carey D, Gerhard G, Cubells J Sadee W. Regulatory polymorphisms in DBH affect peripheral gene expression and sympathetic phenotypes. Under Review at Circulation Research. 2. Barrie ES, Lodder M, Weinreb P, Buss J, Rajab A, Adin C, Mi QS, Hadley GA. Role of CD103 in the development of autoimmune diabetes in NOD mice. Submitted to Journal of Endocrinology. 3. Barrie ES, Smith RM, Sanford JC, and Sadee W. (2012) mrna Transcript Diversity Creates New Opportunities for Pharmacological Intervention, Molecular Pharmacology, 81(5): Kempkes R, Stofko E, Lam K, Snell E. (2008) Glycerol concentrations required for the successful vitrification of cocktail conditions in a high-throughput crystallization screen, Acta Crystallographica D, 64(Pt 3): Coling D, Ding D, Young R, Lis M, Stofko E, Blumenthal K and Salvi R (2007) Proteomic analysis of cisplatininduced cochlear damage: Methods and early changes in protein expression, Hearing Res, 226,

7 AWARDS AND HONORS 2014 Finalist for Hayes Graduate Research Forum, Oral presentation 2013 Chauncey D. Leake Award for Excellence in Pharmacology 2013 Delta Gamma Foundation Fellowship Award 2013 Distinguished University Fellow, final year 2009 Finalist for SIB (Systems and Integrative Biology) Training Grant Distinguished University Fellowship Recipient, The Ohio State University nd place Michelson-Morley Biology Research Competition 2007 Grant from Howard Hughes Medical Institute for SPUR (Summer Program in Undergraduate Research) FUTURE PLANS Elizabeth will continue working in her current lab for the next few months to complete her research projects and publications while interviewing for postdoc positions. Upon completion of her postdoc training, she plans to pursue a scientific research career.

8 [This must be the first line on Page 8] Biomedical Sciences Graduate Program 1170 Graves Hall 333 W. 10 th Avenue Columbus, Ohio 43210