Proneural bHLH neurogenin 2 differentially regulates Nurr1‐induced dopamine neuron differentiation in rat and mouse neural precursor cells in vitro

Roles of Nurr1 and neurogenin 2 (Ngn2) have been shown in midbrain dopamine (DA) neuron development. We present here rat and mouse species‐dependent differences of Nurr1 and Ngn2 actions in DA neuron differentiation. Nurr1 exogene expression caused an efficient generation of tyrosine hydroxylase (TH)‐positive DA cells from rat neural precursor cells (NPCs). Nurr1‐induced TH+ cell yields were low and highly variable depending on the origins of NPCs in mouse cultures. Coexpression of Ngn2 repressed Nurr1‐induced generation of TH+ cells in rat cultures. In clear contrast, a robust enhancement in Nurr1‐induced DA cell yields was observed in mouse NPCs by Ngn2. These findings imply that DA neurons may develop differently in the midbrains of these two species.