TGFB1 and cancer: Also Sp3, a ubiquitously expressed transcription factor and chromatin modifier required for multiple developing organs and cancer (183), Tcf3, which acts downstream of Wnt-beta catenin in the neural tube (76), Smad3, the TgfB-Activin signaling mediator that promotes ventral interneuron fate specification and differentiation (184), as well as Prox1, a repressor which has been shown to suppress Olig2 required for proper motor neuron development in the ventral neural tube (185) were highlighted due to higher activity in the ventral neural tube as compared to other domains (Fig. 4D).