Heart disease is the leading cause of death in the United States. While many factors can contribute to heart disease, stress plays a significant role. To better understand the mechanisms underlying the impact of stress on cardiovascular function, the intent of this thesis is to focus on the adenylate cyclase (AC) family of isoforms as key mediators of stress hormone signaling. AC operates downstream of ß-adrenergic receptor signaling to produce cAMP as a second messenger. There are at least 9 AC isoforms, all of which have different regulatory properties, but it is not clear which of these isoforms are expressed in the developing heart. Thus, there is still much to be discovered. This project seeks to establish a baseline understanding of AC isoform-specific expression patterns in the developing heart to better comprehend the role of these isoforms in development, beginning in the embryonic period and extending into the postnatal and adult ages. To accomplish this, we extracted RNA from flash-frozen hearts at embryonic days 10.5 and 15.5 (e10.5 and e15.5) as well as postnatal days 9 (juvenile), 38 (pre-pubescent) and young adult (2-3 months). Subsequently, quantitative polymerase chain reaction (qPCR) was performed with isoform-specific primers. To verify the amplification, PCR products were run on ethidium bromide gels. Our initial results show that many isoforms are undetected at e10.5, but AC1-3 and AC6-9 were expressed from e15.5 onward. Only AC4 was robustly expressed at all ages, and AC2 and 8 were strongly upregulated during the embryonic period. Our results suggest that AC isoforms 2, 4, and 8 have an important developmental function from early in the embryonic period. Future studies will seek to test the AC isoforms at later postnatal and adult ages and localize AC expression in various areas of the heart.
Bachelor of Science (B.S.)
College of Medicine
Burnett School of Biomedical Sciences
Length of Campus-only Access
Houchin, Lauren A., "Isoform-Specific Expression of Adenylate Cyclase in Cardiac Development" (2020). Honors Undergraduate Theses. 718.