Fig. 7. Schematic summarising the sequential roles of Foxa1/2 during the three different phases of development of mDA neurons from neural stem/progenitor cells. During regional and neuronal specification, Foxa1/2 positively regulates Ngn2 expression in mDA progenitors. Foxa1/2 is subsequently required for Nurr1 and En1 expression in immature mDA neurons and for the expression of aromatic L-amino acid decarboxylase (AADC) and tyrosine hydroxylase (TH) in mature mDA neurons during early and late differentiation.