Tbx1 is required for cardiovascular development in human, mouse and zebra fish. Since the initial recognition of the role of this gene in development, there has been considerable progress in the analysis of mutants that led to novel hypotheses. Tbx1 is a T-box transcription factor required for segmentation of the embryonic pharynx, patterning of the aortic arch, and morphogenesis of the outflow tract of the heart. However, further knowledge acquisition about this gene would be limited if we do not address two fundamental questions: what are the critical players in the regulation of the Tbx1 gene, and what are the targets of the Tbx1 protein. The Tbx1 gene has an exquisitely dynamic regulation, and here we show that this is associated with time-specific roles during embryogenesis. For example, early expression is required for cardiovascular development while late expression is required for thymic organogenesis and palatogenesis. In addition, we show tissue specific requirements for Tbx1 function during cardiovascular development. This proposal builds upon these new data to search for regulators and targets of Tbx1 that are important at the critical times and tissues. ? ? The overall aim is to establish hard links in the genetic pathway within which Tbx1 functions. We believe that this work will lead to genes causing or modifying congenital heart disease. In the first specific aim we will use novel approaches to identify genetic elements necessary for Tbx1 regulation in the pharyngeal endoderm, a key tissue for Tbx1 function, and will also determine if Tbx1 expression in this tissue is sufficient to rescue the cardiovascular abnormalities seen in mutants. In the second specific aim, we will use a combination of transcriptome analysis and chromatin immunoprecipitation assay to identify transcriptional targets. Preliminary data show the power of this approach. In addition, we propose in vitro and in vivo validation of candidate target genes. ? ? This project addresses directly the function of Tbx1 in cardiovascular development as defined by upstream regulation of the gene and transcriptional targets of the protein in relevant tissues. Data should provide the dissection of a genetic network disrupted in DiGeorge and Velocardiofacial syndromes, and possibly in other genetic disorders affecting cardiovascular development. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
7R01HL064832-06
Application #
7072339
Study Section
Genetics of Health and Disease Study Section (GHD)
Program Officer
Schramm, Charlene A
Project Start
2000-04-01
Project End
2010-05-31
Budget Start
2006-06-01
Budget End
2007-05-31
Support Year
6
Fiscal Year
2006
Total Cost
$355,202
Indirect Cost
Name
Texas A&M University
Department
Type
Schools of Medicine
DUNS #
835607441
City
College Station
State
TX
Country
United States
Zip Code
77845
Chen, Li; Fulcoli, Filomena Gabriella; Ferrentino, Rosa et al. (2012) Transcriptional control in cardiac progenitors: Tbx1 interacts with the BAF chromatin remodeling complex and regulates Wnt5a. PLoS Genet 8:e1002571
Vitelli, Francesca; Lania, Gabriella; Huynh, Tuong et al. (2010) Partial rescue of the Tbx1 mutant heart phenotype by Fgf8: genetic evidence of impaired tissue response to Fgf8. J Mol Cell Cardiol 49:836-40
Zhang, Zhen; Baldini, Antonio (2010) Manipulation of endogenous regulatory elements and transgenic analyses of the Tbx1 gene. Mamm Genome 21:556-64
Cao, Huojun; Florez, Sergio; Amen, Melanie et al. (2010) Tbx1 regulates progenitor cell proliferation in the dental epithelium by modulating Pitx2 activation of p21. Dev Biol 347:289-300
Chen, Li; Fulcoli, Filomena Gabriella; Tang, Susan et al. (2009) Tbx1 regulates proliferation and differentiation of multipotent heart progenitors. Circ Res 105:842-51
Lania, Gabriella; Zhang, Zhen; Huynh, Tuong et al. (2009) Early thyroid development requires a Tbx1-Fgf8 pathway. Dev Biol 328:109-17
Caterino, Marianna; Ruoppolo, Margherita; Fulcoli, Gabriella et al. (2009) Transcription factor TBX1 overexpression induces downregulation of proteins involved in retinoic acid metabolism: a comparative proteomic analysis. J Proteome Res 8:1515-26
Vitelli, Francesca; Huynh, Tuong; Baldini, Antonio (2009) Gain of function of Tbx1 affects pharyngeal and heart development in the mouse. Genesis 47:188-95
Fulcoli, F Gabriella; Huynh, Tuong; Scambler, Peter J et al. (2009) Tbx1 regulates the BMP-Smad1 pathway in a transcription independent manner. PLoS One 4:e6049
Xu, Huansheng; Baldini, Antonio (2007) Genetic pathways to mammalian heart development: Recent progress from manipulation of the mouse genome. Semin Cell Dev Biol 18:77-83

Showing the most recent 10 out of 18 publications