Establishment and controlled differentiation of neural crest stem cell lines using conditional transgenesis.

Murine neural crest stem cells (NCSCs) are a multipotent transient population of stem cells. After being formed during early embryogenesis as a consequence of neurulation at the apical neural fold, the cells rapidly disperse throughout the embryo, migrating along specific pathways and differentiating into a wide variety of cell types. In vitro the multipotency is lost rapidly, making it difficult to study differentiation potential as well as cell fate decisions. Using a transgenic mouse line, allowing for spatio-temporal control of the transforming c-myc oncogene, we derived a cell line (JoMa1), which expressed NCSC markers in a transgene-activity dependent manner. JoMa1 cells express early NCSC markers and can be instructed to differentiate into neurons, glia, smooth muscle cells, melanocytes, and also chondrocytes. A cell-line, clonally derived from JoMa1 culture, termed JoMa1.3 showed identical behavior and was studied in more detail. This system therefore represents a powerful tool to study NCSC biology and signaling pathways. We observed that when proliferative and differentiation stimuli were given, enhanced cell death could be detected, suggesting that the two signals are incompatible in the cellular context. However, the cells regain their differentiation potential after inactivation of c-MycER(T). In summary, we have established a system, which allows for the biochemical analysis of the molecular pathways governing NCSC biology. In addition, we should be able to obtain NCSC lines from crossing the c-MycER(T) mice with mice harboring mutations affecting neural crest development enabling further insight into genetic pathways controlling neural crest differentiation.