My long-term career goal is to become a productive and impactful independent investigator in the field of craniofacial development, by conducting cutting-edge, multidisciplinary research to better understand the genetic, molecular, and cellular mechanisms of craniofacial development and disorders. The goal of my research is to improve human health by elucidating disease mechanisms and contributing towards efforts to develop therapeutic strategies. This application will provide the framework to achieve these goals through a coordinated career development plan that utilizes the expertise of a diverse team of mentors and advisors, and the supplemental training opportunities provided by coursework and conferences. These factors are woven into my research strategy addressing important questions in craniofacial development and mechanisms of disorders and expands my training into new areas that are essential for my transition to an independent researcher career. This includes becoming an expert in genetic and transgenic models of zebrafish, genome- wide sequencing approaches like single cell ATAC-seq and ChIP-seq, and human craniofacial anatomy. My mentor team, led by Drs. Clouthier and Nichols, will provide valuable guidance throughout the training plan, including the academic job search and career transition process. Moreover, this training will be carried out at in a stellar research environment in the Department of Craniofacial Biology, and the University of Colorado Anschutz Medical Campus, that collectively have the resources, core facilities, and faculty members needed to ensure the success of this career development plan. This application will address important yet unstudied events in intracellular signaling downstream of the Endothelin receptor type A (EDNRA) that establishes patterning domains along the dorsal-ventral (D-V) axis of pharyngeal arch 1 (PA1). EDNRA signaling is required for lower jaw development and is disrupted in a human craniofacial disorder called Auriculocondylar syndrome (ARCND). EDNRA can signal through all four classes of G proteins, though how dynamic use of different G proteins by EDNRA to pattern different domains of PA1 is unknown and extremely difficult to study. This proposal will use three aims to test the hypothesis that the Gq/11 class exclusively patterns the intermediate domain of PA1, and that Gq/11 regulates patterning gene expression by inducing genome-wide changes to chromatin accessibility. Aim 1 will use genetic and transgenic approaches to determine whether Gq/11 is necessary and sufficient for intermediate domain patterning. Aim 2 will use multimodal single-cell analysis to define cis-regulatory elements and gene regulatory networks controlled by Gq/11. Aim 3 will use zebrafish models of ARCND to understand how disease alleles impact EDNRA-Gq/11 signaling. Furthermore, this information will be used to better understand human cases of ARCND. Collectively, this comprehensive research training and career d...