Work in model organisms has revealed that a small number of signal transduction pathways, including the Wnt/b-catenin pathway, play key roles throughout development, as well as in tissue repair and stem cell homeostasis in adults. Interestingly, the composition of the Wnt/b-catenin pathway differs in distinct cellular contexts, depending on expression of unique modifiers of the signaling pathway, or expression of different isoforms of conserved pathway components. We and others have evidence (see Preliminary studies) that Wnt/b-catenin signaling is repressed in pluripotent human embryonic stem cells (hESCs) undergoing selfrenewal, and that signaling is active during differentiation into both early and later mesodermal cell lineages. We hypothesize that context-dependent modifiers of Wnt/b-catenin signaling play key roles in the self-renewal and differentiation of hESCs. The initial goal of this proposal is to test the hypothesis that context-dependent modulators of Wnt/b-catenin signaling play key roles in regulating self-renewal and differentiation in hESCs. We believe that pursuit of this goal will reveal detailed mechanisms by which Wnt/beta-catenin signaling regulates self-renewal and specification of cell fate in hESCs. Our second goal is to expand our investigation of the roles of signal transduction pathways in stem cells to include the Hedgehog, Notch, and TGFb pathways, using novel multiplexed fluorescent reporters to enable simultaneous monitoring of multiple pathways in live cells. We believe that the development of the technology to simultaneously visualize the state of activity of multiple signaling pathways in live cells will have numerous uses in studies of signaling pathways in normal and diseased tissues.

Public Health Relevance

Human embryonic stem cells (hESCs) have the capacity to renew themselves in culture and to differentiate into different cell types, such as heart or nervous system. Wnts are secreted proteins that act as messengers between cells, and which can instruct hESCs to alter whether they self-renew or whether they differentiate. We propose experiments that will provide insights into the mechanisms by which Wnts control self renewal and differentiation of hESCs.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Program Projects (P01)
Project #
5P01GM081619-07
Application #
8598892
Study Section
Special Emphasis Panel (ZRG1)
Project Start
2013-12-01
Project End
2017-11-30
Budget Start
2013-12-01
Budget End
2014-11-30
Support Year
7
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of Washington
Department
Type
DUNS #
City
Seattle
State
WA
Country
United States
Zip Code
98195
Ellen Kreipke, Rebecca; Wang, Yuliang; Miklas, Jason Wayne et al. (2016) Metabolic remodeling in early development and cardiomyocyte maturation. Semin Cell Dev Biol 52:84-92
Hofsteen, Peter; Robitaille, Aaron M; Chapman, Daniel Patrick et al. (2016) Quantitative proteomics identify DAB2 as a cardiac developmental regulator that inhibits WNT/β-catenin signaling. Proc Natl Acad Sci U S A 113:1002-7
Ruan, Jia-Ling; Tulloch, Nathaniel L; Razumova, Maria V et al. (2016) Mechanical Stress Conditioning and Electrical Stimulation Promote Contractility and Force Maturation of Induced Pluripotent Stem Cell-Derived Human Cardiac Tissue. Circulation 134:1557-1567
Pioner, Josè Manuel; Racca, Alice W; Klaiman, Jordan M et al. (2016) Isolation and Mechanical Measurements of Myofibrils from Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Stem Cell Reports 6:885-96
Xu, Zhuojin; Robitaille, Aaron M; Berndt, Jason D et al. (2016) Wnt/β-catenin signaling promotes self-renewal and inhibits the primed state transition in naïve human embryonic stem cells. Proc Natl Acad Sci U S A 113:E6382-E6390
Roberts, Meredith A; Tran, Dominic; Coulombe, Kareen L K et al. (2016) Stromal Cells in Dense Collagen Promote Cardiomyocyte and Microvascular Patterning in Engineered Human Heart Tissue. Tissue Eng Part A 22:633-44
Kolwicz Jr, Stephen C; Odom, Guy L; Nowakowski, Sarah G et al. (2016) AAV6-mediated Cardiac-specific Overexpression of Ribonucleotide Reductase Enhances Myocardial Contractility. Mol Ther 24:240-50
Fernandes, Sarah; Chong, James J H; Paige, Sharon L et al. (2015) Comparison of Human Embryonic Stem Cell-Derived Cardiomyocytes, Cardiovascular Progenitors, and Bone Marrow Mononuclear Cells for Cardiac Repair. Stem Cell Reports 5:753-62
Xing, Yalan; Su, Tin Tin; Ruohola-Baker, Hannele (2015) Tie-mediated signal from apoptotic cells protects stem cells in Drosophila melanogaster. Nat Commun 6:7058
Brzezinski, Joseph A; Reh, Thomas A (2015) Photoreceptor cell fate specification in vertebrates. Development 142:3263-73

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