The early morphogenetic mechanisms involved in heart formation are evolutionarily conserved. To identify novel cardiogenic genes, we performed a large-scale genetic screen in Drosophila. We discovered a unique cardiac defect, called broken hearted (bro), in which pericardial cells and cardioblasts dissociate, causing loss of cardiac function and embryonic lethality. This phenotype resulted from mutations in genes encoding HMG-CoA reductase and its downstream enzymes in the mevalonate pathway, as well as G protein G31, which is geranylgeranylated, thus representing an end point of isoprenoid biosynthesis. Identification of the essential role of C in cardiac morphogenesis opened a door to discovery of the entire G protein genetic pathway required for cardiac morphogenesis. Here, we will investigate the functional mechanism of G31, and identify the G1 and G2 partners that form the cardiac heterotrimeric G protein complex with G31. From our screen, we also identified two G-protein coupled receptors (GPCRs) involved in this process. We will investigate the roles of these GPCRs using cardiac cell type specific rescue system established in our preliminary studies. Our screen also identified two bro mutations disrupting genes encoding septate junction components, indicating that septate junction formation is involved in cardiac morphogenesis. We will characterize the cell-cell junctions of Drosophila heart using electron microscopy and study the role of septate junction proteins during heart development. We will also examine how the G protein signaling mutants affect septate junction formation in the heart. These studies will fill a significant gap in the research field of heart development, and promote our understanding of the molecular mechanism of congenital heart disease. Narrative: Heart development is controlled by evolutionarily conserved genetic network. To identify genes in this network, we performed a large-scale genetic screen in Drosophila and identified a group of highly conserved genes required for heart formation. Studies of these genes promote our understanding of heart development and mechanism of congenital heart disease.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL090801-02
Application #
7554644
Study Section
Cardiovascular Differentiation and Development Study Section (CDD)
Program Officer
Schramm, Charlene A
Project Start
2008-02-01
Project End
2013-01-31
Budget Start
2009-02-01
Budget End
2010-01-31
Support Year
2
Fiscal Year
2009
Total Cost
$342,000
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
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Zhu, Jun-Yi; Fu, Yulong; Richman, Adam et al. (2017) Validating Candidate Congenital Heart Disease Genes in Drosophila. Bio Protoc 7:
Zhu, Jun-Yi; Heidersbach, Amy; Kathiriya, Irfan S et al. (2017) The E3 ubiquitin ligase Nedd4/Nedd4L is directly regulated by microRNA 1. Development 144:866-875
Zhu, Shasha; Han, Zhe; Luo, Yan et al. (2017) Molecular mechanisms of heart failure: insights from Drosophila. Heart Fail Rev 22:91-98
Zhu, Jun-Yi; Fu, Yulong; Nettleton, Margaret et al. (2017) High throughput in vivo functional validation of candidate congenital heart disease genes in Drosophila. Elife 6:
Jiang, Z; Li, F; Wan, Y et al. (2016) LASS5 Interacts with SDHB and Synergistically Represses p53 and p21 Activity. Curr Mol Med 16:582-90
Chen, Zhimin; Zhu, Jun-Yi; Fu, Yulong et al. (2016) Wnt4 is required for ostia development in the Drosophila heart. Dev Biol 413:188-98
Patel, Meghna V; Zhu, Jun-Yi; Jiang, Zhiping et al. (2016) Gia/Mthl5 is an aorta specific GPCR required for Drosophila heart tube morphology and normal pericardial cell positioning. Dev Biol 414:100-7
Fulga, Tudor A; McNeill, Elizabeth M; Binari, Richard et al. (2015) A transgenic resource for conditional competitive inhibition of conserved Drosophila microRNAs. Nat Commun 6:7279
Gee, Heon Yung; Zhang, Fujian; Ashraf, Shazia et al. (2015) KANK deficiency leads to podocyte dysfunction and nephrotic syndrome. J Clin Invest 125:2375-84

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