br Conclusion br Author contributions br Acknowledgements We

Conclusion
Author contributions
Acknowledgements We thank nicotinic acetylcholine receptor USC Center for Craniofacial Molecular Biology (CCMB) for their extensive guidance and teaching in biochemical techniques. We acknowledge Laurel Fisher, PhD for her contribution to statistical analysis of the data. We acknowledge Bridget Samuels, PhD for her contribution to the manuscript revision process. We also acknowledge Michael Cowan, MS, of the USC Department of Stem Cell Biology and Regenerative Medicine for his contributions to data analysis. We acknowledge Dr. Anping Xia for her assistance in establishing primary cell cultures at Stanford University. G.B. gratefully acknowledges fellowship support from the USC Keck School of Medicine Dean's Research Scholar Program. R.H. gratefully acknowledges grant support from the California Institute for Regenerative Medicine (CIRM), Bridges to Stem Cell Research Award grant no. EDUC2-08398. Y.C. gratefully acknowledges grant support from the NIH, grant no. R37DE012711 and R01DE025221. This study was also supported by a electron acceptor grant from the Donald E. and Delia B. Baxter Foundation and the Research Scholar Award from the American Association of Facial Plastic & Reconstructive Surgery (Dr. Pepper).