Michael Dennis, Ph.D.- Principal Investigator
Ph.D., Biochemistry, University of Texas, Austin TX
Dr. Dennis received his doctorate for research that explored post-translational modification of eukaryotic translation initiation factors in plants. As a postdoctoral fellow, he worked in the laboratory of Drs. Leonard (Jim) Jefferson and Scot Kimball at Penn State College of Medicine to determine the impact of diabetes on hepatic mRNA translation. He discovered a novel mechanism whereby hyperglycemia causes a shift in the selection of mRNAs for translation leading to increased synthesis of pro-angiogenic factors, such as vascular endothelial growth factor (VEGF). As an independent investigator, his research has focused on the molecular events that contribute to diabetic retinopathy, as increased VEGF expression has a causal role its pathology.
Siddharth Sunilkumar, Ph.D.- Postdoctoral Fellow
Ph.D., Toxicology, St. John’s University, Queens NY
Dr. Sunilkumar received his doctorate for work that explored the impact of diabetes on glucose transport in the kidney. He joined the Dennis Lab in 2019 and has explored the impact of non-canonical glucagon receptor-mediated signaling and the stress response protein REDD1 on mTORC1 activation. He is supported by an American Diabetes Association Postdoctoral Fellowship to evaluate the role of REDD1 in diabetes-induced podocyte defects in the kidney.
Sandeep Subrahmanian, Ph.D.- Postdoctoral Scholar
Ph.D., Biochemistry, University of Mysore
Dr. Subrahmanian has a background in growth factor signaling events that contribute to epithelial to mesenchymal transition. He is working to explore signaling events that contribute to retinal oxidative stress and inflammation in diabetic retinopathy. He recently received a BrightFocus Foundation Postdoctoral Fellowship to extend his discoveries into a murine model of dry age-related macular degeneration.
Allyson Toro- Laboratory Manager
B.S., Biology, Salem State University, Salem MA
Allyson joined the Dennis Lab in 2015 as a research support associate. She developed a unique RiboTag mouse model to facilitate cell type specific investigation of mRNA translation in genetically identified retinal Müller glia within the intact retina. Her model will address a major limitation in the field of retinopathy, as the retina consists of dozens of different cell types with widely distinct functions and corresponding gene expression profiles. She has extensive experience in molecular biology including mRNA isolation, preparation of cDNAs, cell transfection, RT-PCR, Northern and Southern blots, Western blot analysis, and management of transgenic rodent colonies.
Shaunaci Stevens- Graduate Student
B.S., Biological Sciences, North Carolina State University NC
Shaunaci is a Biomedical Sciences Graduate student in the Cellular and Integrative Physiology Core Option. She joined the Dennis Lab in the summer of 2020 after completing a rotation project that explored translational regulation of the mRNA encoding ApoB. Shaunaci is supported by an F31 NRSA from NHLBI to investigate a role for REDD1 in heart disease.
Ashley VanCleave- Graduate Student
B.S., Biochemistry, Briarcliff University, Sioux City IA
Ashley is a Biomedical Sciences candidate that joined the lab in the summer of 2021. She is exploring mitochondrial dysfunction in retinal glia and its impact on the progression of diabetic retinopathy. Her research interests include metabolism, cell signaling, and mitochondrial dynamics.
Christopher McCurry- Graduate Student
B.A., Biology, Mount Saint Mary College, Newburgh NY
Christopher is a Biomedical Sciences PhD candidate from Newburgh, New York. He joined the Dennis Lab in the fall of 2021, and is currently focused on the role inflammation plays in the development of diabetic retinopathy. Christopher’s research interests include gene expression regulation, cell signaling, and inflammation.
Esma Yerlikaya, M.D.- Graduate Student
M.D., Ankara University Faculty of Medicine, Turkey
Dr. Yerlikaya is a Biomedical Sciences Graduate student that joined the lab in the Spring of 2022. She is enthusiastic about combining her clinical knowledge with basic science. She is particularly interested in vascular changes that occur in late-stage diabetic retinopathy. Her project uses tools such as a hypoxia chamber and in-vitro permeability assays to better understand the molecular events that cause diabetic retinopathy.
Lab Alumni
William Miller, Ph.D.- Graduate Student
Ph.D, Biomedical Sciences, Penn State College of Medicine
Dr. Miller graduated from the Biomedical Sciences PhD program Translational Therapeutics tract in December of 2021. While in the lab, he was supported by an F31 pre-doctoral fellowship from the National Eye Institute to explore a role for REDD1 in the defective antioxidant response that is associated with diabetic retinopathy. He has since gone on to pursue a postdoc at Harvard Medical School.
Joseph Giordano- Research Technician
B.S., Biology, Gwynedd Mercy University PA
Joseph worked in the Dennis Lab as part of the SUIRP program in 2018 and 2019. During that time he explored the impact of REDD1 on Nrf2 protein degradation. In May of 2020, he completed his undergraduate degree, and returned to the lab as a research technician. He has since gone on to medical school.
Sadie Dierschke, Ph.D.- Graduate Student
Ph.D., Biomedical Sciences, Penn State College of Medicine PA
In May of 2020, Sadie graduated from the Clinical and Translational Sciences dual-title PhD program. While in the lab, she explored the impact of protein O-GlcNAcylation on retinal gene expression and discovered that Ang1-7 signaling acts to repress enzymatic activity of the O-GlcNAc transferase. Dr. Dierschke’s first author JBC manuscript demonstrates that augmented O-GlcNAcylation alters tranlsation of ~19% of the retinal transcriptome. She has since gone on to pursue a career in scientific writing.
Weiwei Dai, Ph.D.- Postdoctoral Fellow
Ph.D., Biology, Institut National de la Recherche Agronomique, Pau, France
While in the Dennis Lab, Dr. Dai explored the role of dyslipidemia in the development of diabetic retinopathy. He found that retinas of mice fed a high-fat diet exhibited markers of inflammation and insulin resistance prior to the onset of hyperglycemia. Dr. Dai was the first to report that diets high in saturated fats cause changes in retinal sphingolipid profiles in association with attenuation of pro-survival kinase signaling and increased retinal cell death. He is presently an Assistant Professor at Xi’an Jiaotong-Liverpool University in Suzhou, China.
Joshua Moore- Graduate Student
M.S., Biomedical Sciences, Penn State College of Medicine
As the inagural graduate student of the Dennis Lab, Joshua evaluated the effect of glucosamine on insulin action in retinal Müller cells. Joshua pioneered development of many of our CRISPR retinal cell lines. He graduated with an M.S. from the Biomedical Sciences program after presenting his work at the annual meeting of the American Diabetes Association and having his studies published in Cellular Signaling.
Chen Yang, Ph.D.- Research Associate
Doctorate of Physical Therapy, University of Southern California, Los Angeles CA
As a founding member of the Dennis Lab, Dr. Yang performed functional assessment of retinal defects in transgenic mice. She was the first to discover that unlike diabetic wild-type mice, diabetic mice deficient for REDD1 fail to exhibit deficits in retinal function.
Summer Undergraduate Research Interns-
Efosa Omorogbe, Mount Saint Mary, 2023
Maria Gonzalez Aguiar, Davidson University, 2022
Andrea Lopez, University of Florida, 2021
Sarah Stenske, Franklin and Marshall, 2018
Ivan Ezeigbo, Minerva Schools at Keck Graduate Institute, 2017
Maria L. Mihailescu, University of Illinois, 2016