Endothelin signaling activates neural crest gene expression via a MEF2C-dependent positive-feedback transcriptional mechanism
Endothelin signaling is one of the essential signaling pathways that control vertebrate development. Dysregulated Endothelin signaling plays an important role in the pathogenesis of human diseases such as Hirschsprung’s disease, pulmonary hypertension and cancer. However, the downstream transcriptional program and transcriptional factors of Endothelin signaling have been incompletely understood. Here, we used RNA-sequencing to identify the genes regulated by Endothelin signaling in the neural crest, where Endothelin signaling functions primarily during development. We further demonstrate that Endothelin induces gene expression through the de-repression of the MADS Box transcription factor MEF2C. Moreover, in the Mef2c gene locus, we identified an Endothelin responsive cis-regulatory element which functions as a central component of an Endothelin-MEF2C positive feedback transcriptional mechanism that regulates downstream gene expression. Overall design: We performed RNA-sequencing experiment on genetically labeled Neural crest cells that treated with Endothelin-1 (or PBS) in the presence or absence of Mef2c. Specifically, we characterized Endothelin-1 regulated genes by comparing gene expression profile in Endothelin-1 treated wild type (sample 4-6) neural crest cells and PBS treated wild type (sample1-3) neural crest cells (gene list 1). We also characterized all Mef2c dependent genes in our Endothelin-1 induction experiment by comparing gene expression profile in Endothelin-1 treated wild type (sample 4-6) neural crest cells and Endothelin-1 treated Mef2c neural crest conditional knockout (sample7-9) neural crest cells (gene list 2). We identify Mef2c-dependent, Endothelin-1 regulated genes by overlapping gene list 1 to gene list 2.