The long-term goal of this project is to understand the role of endothelin-A receptor (Ednra) signaling in cephalic neural crest cells (NCCs) during craniofacial morphogenesis. NCCs within the pharyngeal arches are patterned by a wide array of transcription factors and signaling molecules. Expression of the genes encoding these proteins are generally confined to specific """"""""domains"""""""" within the arches, though very little is known about how these domains are established. Endothelin-1 (Ednl)-induced signaling of Ednra is crucial for NCC patterning during lower jaw development, as Edn1-/- and Ednra-/- embryos die at birth from severe craniofacial birth defect that include homeotic transformation of first mandibular first arch-derived structures into more maxillary first arch-like structures, indicating a loss of cell identity. These changes are preceded by disruption of normal mandibular arch gene expression. Our preliminary data indicates that Ednra signaling may be required for NCCs to populate the distal arch. We hypothesize that Edn1/Ednra signaling creates a """"""""development domain"""""""" within the mandibular arch by two methods: 1) guiding NCCs into specific mandibular arch compartments by establishing an Edn1 gradient within the arch and 2) inducing mandibular-specific gene expression while inhibiting maxillary-specific gene expression, with the induced gene expression dependent on the source of Edn1 within the arch. We will address these hypotheses using a variety of approaches.
In Aim 1, we will use an inducible gene expression system in the mouse to target Edn1 expression to NCCs, allowing us to disrupt any Edn1 gradient in the pharyngeal arches.
In Aim 2, we will use Cre/loxP technology in the mouse to individually inactivate the Edn1 gene in its source tissues within the arches.
In Aim 3, we will use the Dlx1/Dlx2 and Ednra mutant strains and a novel inducible Dlx2 transgenice mouse strain to examine how Edn1/Ednra signaling establishes a developmental program in the mandibular arch. Together, these approaches will hopefully elucidate the functional significance of endothelin signaling during facial development, further our understanding of the molecular basis of mandibular arch patterning and help explain the molecular basis behind human birth defects that affect the face.

National Institute of Health (NIH)
National Institute of Dental & Craniofacial Research (NIDCR)
Research Project (R01)
Project #
Application #
Study Section
Skeletal Biology Development and Disease Study Section (SBDD)
Program Officer
Scholnick, Steven
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Colorado Denver
Schools of Dentistry
United States
Zip Code
Tavares, Andre L P; Clouthier, David E (2015) Cre recombinase-regulated Endothelin1 transgenic mouse lines: novel tools for analysis of embryonic and adult disorders. Dev Biol 400:191-201
Gordon, Christopher T; Weaver, K Nicole; Zechi-Ceide, Roseli Maria et al. (2015) Mutations in the endothelin receptor type A cause mandibulofacial dysostosis with alopecia. Am J Hum Genet 96:519-31
Feng, Weiguo; Choi, Irene; Clouthier, David E et al. (2013) The Ptch1(DL) mouse: a new model to study lambdoid craniosynostosis and basal cell nevus syndrome-associated skeletal defects. Genesis 51:677-89
Clouthier, David E; Passos-Bueno, Maria Rita; Tavares, Andre L P et al. (2013) Understanding the basis of auriculocondylar syndrome: Insights from human, mouse and zebrafish genetic studies. Am J Med Genet C Semin Med Genet 163C:306-17
Tavares, Andre L P; Garcia, Elvin L; Kuhn, Katherine et al. (2012) Ectodermal-derived Endothelin1 is required for patterning the distal and intermediate domains of the mouse mandibular arch. Dev Biol 371:47-56
Clouthier, David E; Garcia, Elvin; Schilling, Thomas F (2010) Regulation of facial morphogenesis by endothelin signaling: insights from mice and fish. Am J Med Genet A 152A:2962-73
Ruest, Louis-Bruno; Clouthier, David E (2009) Elucidating timing and function of endothelin-A receptor signaling during craniofacial development using neural crest cell-specific gene deletion and receptor antagonism. Dev Biol 328:94-108
Clouthier, David E; Gray, Josie; Artinger, Kristin Bruk (2008) Micromanaging Palate Development. Perspect Speech Sci Orofac Disord 18:62-72
Hendershot, Tyler J; Liu, Hongbin; Clouthier, David E et al. (2008) Conditional deletion of Hand2 reveals critical functions in neurogenesis and cell type-specific gene expression for development of neural crest-derived noradrenergic sympathetic ganglion neurons. Dev Biol 319:179-91
Abe, Makoto; Ruest, Louis-Bruno; Clouthier, David E (2007) Fate of cranial neural crest cells during craniofacial development in endothelin-A receptor-deficient mice. Int J Dev Biol 51:97-105

Showing the most recent 10 out of 14 publications