Poster abstracts

Poster number 141 submitted by Evan Rogers

Role of Dhx36/G4R1 in coronary angiogenesis and heart development

Evan M. Rogers (Department of Biology, Ball State University), Frank Bogan (Department of Biology, Ball State University), Kamal Baral (Department of Biology, Ball State University), Brendan W. Jones, Michael Reisinger, Bryce Kushel (Department of Biology, Ball State University), Philip J. Smaldino and Bikram Sharma (Department of Biology, Ball State University)

Abstract:
Coronary vessels are blood vessels that deliver oxygen and nutrients to the heart muscle, and they develop by angiogenesis, the process of new blood vessel formation. Since coronary vessels feed the heart muscle, proper formation of these blood vessels is essential for heart development. Dysfunctional or damaged coronary arteries are the primary cause of cardiac failure, the leading cause of death in adults, so it is vital to understand the molecular underpinnings of coronary vessel formation. The embryonic heart is an excellent model to study this because it allows us to capture the molecular details of how coronary vessels are first established in the heart. Using an embryonic mouse heart as a model system, we study the developmental mechanisms of coronary vessel formation. In our most recent investigation into the molecular mediators of this process, we identified Dhx36 as a potential regulator. Dhx36 (aliases: G4R1 and RHAU) encodes an RNA helicase that unwinds G-quadruplex structures in DNA and RNA. Previously, substantial cardiovascular defects have been shown to arise when Dhx36 is knocked out in mice embryos, however its exact role in coronary vessel formation is still unknown. Our preliminary study from a Dhx36 conditional knockout in the vasculature of a mouse embryo revealed significant delay in coronary vessel expansion and coronary endothelial differentiation. In addition, we observed a reduced thickness of the myocardium. Our future studies are aimed at characterizing this exact role and the underlying molecular mechanisms by which Dhx36 regulates coronary angiogenesis. An improved understanding of the mechanisms of coronary vessel formation could be beneficial to strategizing the repair and regeneration of damaged coronary vessels within the adult heart.

Keywords: Dhx36G4R1, coronary angiogensis, heart development