Current Projects Craniofacial Morphogenesis. The primary objective is to investigate the fundamental mechanisms underlying craniofacial development, including development of cranial neural crest, cell fate determination and differentiation of mesenchymal stem cells, calvarial morphogenesis, tooth development and palatogenesis. Breast Development and Tumorigenesis. The main focus is to investigate cellular signaling in normal development and neoplastic transformation of the mammary gland. We are particularly interested in roles of mammary stem cells and parity-induced mammary progenitors in these processes. Stem Cell Biology. This is an integral part of our projects studying the genetic control of cellular signals and signal transduction mechanisms underlying development of lineage-specific stem cells and niches in skeletal, reproductive, skin and nerve systems. Ubiquitin-like Modifiers. A multidisciplinary approach has been initiated to study SUMO modification in mammalian development and disease. Studies include SUMO-mediated regulation in embryonic and extraembryonic development, cardiovascular, skeletal and neurological disorders, and cancers. Wnt Production and Signaling. This project deciphers the regulatory mechanism underlying the making of Wnt and its signaling effects in signal-producing and signal-receiving cells. Our current focus is to investigate the reciprocal regulation of Wnt and Gpr177/mouse Wntless in development of various organs as well as pathogenesis of human diseases. Funding Support: National Cancer Institute, National Institute of Dental and Craniofacial Research, National Institutes of Health, Breast Cancer Research Program, Department of Defense, NYSTEM and March of Dimes.