Assistant Professor

550 Mosler Hall, Hamilton Campus
schumaj@MiamiOH.edu513-727-3447

Biographical Information

The cardiovascular system is the first organ system to form and function in animals. Improper formation of the cardiovascular system during fetal development leads to congenital heart defects, which occur in up to 1% of live human births. We study the molecular signaling networks that guide development of the endocardium, which is the inner vascular lining of the heart that is surrounded by the muscular myocardium. The endocardium connects the heart to the blood vessel network, establishing a closed circuit for blood flow. It also plays a key role in forming heart valves, which ensure that blood flows in the correct direction through the heart. Although the endocardium is indispensable for cardiovascular system function, we do not fully understand how endocardium is formed in the developing embryo.

The Schumacher Lab uses the zebrafish as a model organism to focus on two key steps of endocardial formation:  how a specific subset of cells in the early embryo is instructed to become endocardium, and how endocardial cells move to form the proper shape. We combine embryology, molecular biology, genetics, and genome editing techniques to uncover the molecular mechanisms driving both of these processes. We use these tools to better understand how endocardial cells communicate with their surrounding environment, called the extracellular matrix, to drive specific patterns of gene expression and to promote organized cell migrations that form the proper heart structure.

Zebrafish are an outstanding model organism for studying cardiovascular development and function due to the optical clarity of embryos, availability of genetic mutants and fluorescent transgenes, and ease of genome editing. Additionally, zebrafish produce hundreds of embryos per week that are easily manipulated through microinjection and chemical treatment. The transparent embryos allow us to visualize fluorescently labeled heart and blood vessel cells within living embryos, so we can track their location and behaviors over time. Ultimately, understanding the molecular signaling pathways that instruct the proper formation of the cardiovascular system will allow us to better understand the reasons why heart defects occur, which we hope will lead to better prevention strategies and treatments.

Education

Ph.D., University of Pennsylvania, 2007

Courses Taught

• Human Anatomy and Physiology (BIO 171/172)

Selected Publications

• Pociute, K., Schumacher, J.A., Sumanas, S. (2019) Clec14a genetically interacts with Etv2 and Vegf signaling during vasculogenesis and angiogenesis in zebrafish. BMC Developmental Biology 19(1):6.
• Casie Chetty, S., Rost, M.S., Enriquez, J.R., Schumacher, J.A., Baltrunaite, K., Rossi, A., Stainier, D.Y., and Sumanas, S. (2017) Vegf signaling promotes vascular endothelial differentiation by modulating etv2 expression. Developmental Biology 424(2): 147-161.
• Palencia-Desai, S., Rost, M.S., Schumacher, J.A., Ton, Q.T., Craig, M.P., Baltrunaite, K., Koenig, A., Wang, J., Poss, K.D., Chi, N.C., Stainier, D.Y.R., and Sumanas, S. (2015)  Myocardium and BMP signaling are required for endocardial differentiation.  Development 142(13): 2304-2315.
• Schumacher, J.A., Zhao, E.J., Kofron, M.J., and Sumanas, S. (2014)  Two color fluorescent in situ hybridization using chromogenic substrates in zebrafish.  Biotechniques 57(5): 254-256.
• Glenn, N.O.*,Schumacher, J.A*., Kim, H.J., Zhao, E., Skerniskyte, J., and Sumanas, S. (2014)  Distinct regulation of the anterior and posterior myeloperoxidaseexpression by Etv2 and Gata1 during primitive neutropoiesis in zebrafish. Developmental Biology 393(1): 149-159. *indicates co-first authors
• Schumacher, J.A.*, Bloomekatz, J.*, Garavito-Aguilar, Z.V., and Yelon, D. (2013)  tal1 regulates the formation of intercellular junctions and the maintenance of identity in the endocardium. Developmental Biology 383(2): 214-226. *indicates co-first authors
• Kohli, V.*, Schumacher, J.A.*, Palencia Desai, S., Rehn, K., and Sumanas, S. (2013)  Arterial and venous progenitor cells of the major axial vessels originate at distinct locations.  Developmental Cell 25(2): 196-208. *indicates co-first authors