Neurons in three of the clusters project to the mushroom body neuropil: PAM neurons project to the medial portion of the horizontal lobes PPL1 neurons project to the vertical lobes, the junction area, the heel and distal peduncle and PPL2ab neurons project to the calyx. Eight clusters of putative dopaminergic neurons were characterized. We examined tyrosine hydroxylase ( TH-GAL4) expression and anti-TH immunoreactivity in the Drosophila protocerebrum and characterized single cell clones of the TH-GAL4 neurons.
