Kouji Yasuyama    Department   Kawasaki University of Medical Welfare  ,    Position   Professor with Special Assignment
Article types	原著
Language	English
Peer review	Peer reviewed
Title	Synaptic connections of PDF-immunoreactive lateral neurons projecting to the dorsal protocerebrum of Drosophila melanogaster.
Journal	Formal name：The Journal of comparative neurology Abbreviation：J Comp Neurol ISSN code：00219967/10969861
Volume, Issue, Page	518(3),pp.292-304
Author and coauthor	Yasuyama Kouji, Meinertzhagen Ian A.,
Authorship	Lead author
Publication date	2010/02
Summary	Recent studies in Drosophila melanogaster indicate that the neuropeptide pigment-dispersing factor (PDF) is an important output signal from a set of major clock neurons, s-LNvs (small ventral lateral neurons), which transmit the circadian phase to subsets of other clock neurons, DNs (dorsal neurons). Both s-LNvs and DNs have fiber projections to the dorsal protocerebrum of the brain, so that this area is a conspicuous locus for coupling between different subsets of clock neurons. To unravel the neural circuits underlying the fly's circadian rhythms, we examined the detailed subcellular morphology of the PDF-positive fibers of the s-LNvs in the dorsal protocerebrum, focusing on their synaptic connections, using preembedding immuno-electron microscopy. To examine the distribution of synapses, we alsp reconstructed the three-dimentional morphology of PDF-positive varicosities from fiber profiles in the dorsal protocerebrum. The varicosities contained large dense-core vesicles (DCVs), and also numerous small clear vesicles, forming divergent output synapses onto unlabeled neurites. The DCVs apparently dock at nonsynaptic sites, suggesting their nonsynaptic release. In addition, a 3D reconstruction revealed the presence of input synapses onto the PDF-positive fibers. These were detected less frequently than output sites. These observations suggest that the PDF-positive clock neurons receive neural inputs directly through synaptic connections in the dorsal protocerebrum, in addition to supplying dual outputs, either synaptic or via paracrine release of the DCV contents, to unidentified target neurons.
DOI	10.1002/cne.22210