Expression of CiPtf1a in dopamine cells of the sensory vesicle of C. intestinalis larva. Dorsal views of heads of C. intestinalis larvæ expressing CFP in TH cells (pSP-Ci-TH-CFP) (a), as well as the Kaede reporter under the control of the CiPtf1a promoter (pSP-Ci-Ptf1a Kaede) (b) in the sensory vesicle of ascidian larva; merged image (c). Ot : otolith and Oc : ocellus. (anterior to the left, scale bar, 50 µm). Ot, otolith and Oc, ocellus. (scale bar, 50 μm). (c) Schematic drawing of a lateral view of the head and neck of an ascidian larva (the tail is not shown). The head CNS is shaded and divided into sensory vesicle the trunk ganglion. The neuronal populations expressing identified neurotransmitters are grossly shown. The DA coronet cells (pink), also expressing SERT and Ptf1a, are in close relationships with the population III of photoreceptors and one population of cholinergic neurons (yellow). They send processes toward glutamatergic (purple) and GABAergic (green) neurons. The TPH/vMAT expressing cells, which are localized dorso-laterally to the CNS are shown only on the right side. The central motor pattern generator and mostly the cholinergic output neurons are shown.