has characteristic fasciculates with directly develops from receives synaptic input in region medulla LN Pdf neuron l-LNv neuron Neuron of the period-expressing LNv cluster of the adult brain, with a large cell body and generally located more dorsally than the s-LNv neurons (Helfrich-Forster, 1998). There are four of these cells per hemisphere, all of which express Pdf (Helfrich-Forster et al., 2007). These neurons send dendrites through the posterior optic commissure to the contralateral optic lobe, where a few short fibers terminate in the accessory medulla, but most arborize extensively in the medulla itself (Helfrich-Forster, 2005; Helfrich-Forster et al., 2007). These arborizations in the medulla are associated with varicosities. These cells also project to the ipsilateral (adjacent) accessory medulla and its ventral extension, where they arborize extensively. l-vLN large pigment-dispersing hormone-immunoreactive neuron close to medulla While l-LNv neurons fit the definition of pacemaker neurons based on molecular oscillation of Period (FBgn0003068) and Timeless (FBgn0014396) expression, they do not sustain this molecular oscillation when kept in constant darkness (Yang and Sehgal, 2001; Shafer et al., 2002). Synaptobrevin localization supports the assertion that projections through the posterior optic commissure to the contralateral optic lobe are dendritic (Helfrich-Forster et al., 2007). l-LNv lLNv large LNv l-LNv FBbt:00003763 fly_anatomy.ontology VFB:FBbt_00003763 LNv neuron posterior optic commissure pupal l-LNv Pdf neuron bilateral