Transforming growth factors-? are secreted polypeptides that render both physiological and pathological functions. Two receptor tyrosine kinases, T?RI and T?RII mediate the impact of TGF-? signaling on the cell surface. Functional specificity and differences between the two receptors, subsequent to ligand binding have not been rigorously and mechanistically addressed in lung development and disease. We have found that TGF-? signaling through the T?RII plays a critical role in both morphogenesis and injury in the lung. In the mesenchyme, we found T?RII to be required for normal epithelial-mesenchymal communication through Shh. In the epithelium, signaling through T?RII regulates alveolar formation, and is required in Bleomycin-induced lung injury. Based on these concepts, we have formulated the following hypothesis: HYPOTHESIS: Normal lung development and Bleomycin-induced lung injury are dependent on TGF-? signaling through T?RII. The latter hypothesis is supported by the available data and some of its predictions are directly testable by the following four Specific Aims:
Specific aim 1. To Determine the Mechanism of Cross-Talk Between Shh &TGF-? Signaling Pathways.
Specific aim 2. To Identify Components of the TGF-? Pathway That Mediate the Cross-Talk With the Shh Pathway.
Specific aim 3. To Determine the Potential Role of Epithelial T?RII in Pathogenesis of Bleomycin-Induced Murine Model of Pulmonary Fibrosis. Health Relevance: TGF-? is implicated in many lung diseases including Pulmonary Fibrosis and Bronchopulmonary Dysplasia. To our knowledge, the studies proposed in this application are the first to address, cell-specifically (epithelial versus mesenchymal) the contributions of signaling through T?RII to pathogenesis of lung injury.

Public Health Relevance

This project will use specific genetic tools to study the role of TGF-? during lung development and in pathogenesis of neonatal and adult chronic diseases.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-RES-B (02))
Program Officer
Lin, Sara
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Southern California
Schools of Medicine
Los Angeles
United States
Zip Code
Rieger, Megan E; Zhou, Beiyun; Solomon, Nicola et al. (2016) p300/?-Catenin Interactions Regulate Adult Progenitor Cell Differentiation Downstream of WNT5a/Protein Kinase C (PKC). J Biol Chem 291:6569-82
Li, Aimin; Ma, Shudong; Smith, Susan M et al. (2016) Mesodermal ALK5 controls lung myofibroblast versus lipofibroblast cell fate. BMC Biol 14:19
Flodby, Per; Kim, Yong Ho; Beard, LaMonta L et al. (2016) Knockout Mice Reveal a Major Role for Alveolar Epithelial Type I Cells in Alveolar Fluid Clearance. Am J Respir Cell Mol Biol 55:395-406
Xing, Yiming; Wang, Runming; Li, Changgong et al. (2015) PTEN regulates lung endodermal morphogenesis through MEK/ERK pathway. Dev Biol 408:56-65
Al Alam, Denise; El Agha, Elie; Sakurai, Reiko et al. (2015) Evidence for the involvement of fibroblast growth factor 10 in lipofibroblast formation during embryonic lung development. Development 142:4139-50
Li, Guanglei; Flodby, Per; Luo, Jiao et al. (2014) Knockout mice reveal key roles for claudin 18 in alveolar barrier properties and fluid homeostasis. Am J Respir Cell Mol Biol 51:210-22
Kage, Hidenori; Flodby, Per; Gao, Danping et al. (2014) Claudin 4 knockout mice: normal physiological phenotype with increased susceptibility to lung injury. Am J Physiol Lung Cell Mol Physiol 307:L524-36
Li, Aimin; Chan, Belinda; Felix, Juan C et al. (2013) Tissue-dependent consequences of Apc inactivation on proliferation and differentiation of ciliated cell progenitors via Wnt and notch signaling. PLoS One 8:e62215
Li, Changgong; Li, Aimin; Xing, Yiming et al. (2013) Apc deficiency alters pulmonary epithelial cell fate and inhibits Nkx2.1 via triggering TGF-beta signaling. Dev Biol 378:13-24
Zhou, Beiyun; Liu, Yixin; Kahn, Michael et al. (2012) Interactions between ?-catenin and transforming growth factor-? signaling pathways mediate epithelial-mesenchymal transition and are dependent on the transcriptional co-activator cAMP-response element-binding protein (CREB)-binding protein (CBP). J Biol Chem 287:7026-38

Showing the most recent 10 out of 14 publications