Reference - Detail
|Author||Nässel DR, Enell LE, Santos JG, Wegener C, Johard HA.|
|Title||A large population of diverse neurons in the Drosophila central nervous system expresses short neuropeptide F, suggesting multiple distributed peptide functions.|
BACKGROUND:Insect neuropeptides are distributed in stereotypic sets of neurons that commonly constitute a small fraction of the total number of neurons. However, some neuropeptide genes are expressed in larger numbers of neurons of diverse types suggesting that they are involved in a greater diversity of functions. One of these widely expressed genes, snpf, encodes the precursor of short neuropeptide F (sNPF). To unravel possible functional diversity we have mapped the distribution of transcript of the snpf gene and its peptide products in the central nervous system (CNS) of Drosophila in relation to other neuronal markers.
RESULTS:There are several hundreds of neurons in the larval CNS and several thousands in the adult Drosophila brain expressing snpf transcript and sNPF peptide. Most of these neurons are intrinsic interneurons of the mushroom bodies. Additionally, sNPF is expressed in numerous small interneurons of the CNS, olfactory receptor neurons (ORNs) of the antennae, and in a small set of possibly neurosecretory cells innervating the corpora cardiaca and aorta. A sNPF-Gal4 line confirms most of the expression pattern. None of the sNPF immunoreactive neurons co-express a marker for the transcription factor DIMMED, suggesting that the majority are not neurosecretory cells or large interneurons involved in episodic bulk transmission. Instead a portion of the sNPF producing neurons co-express markers for classical neurotransmitters such as acetylcholine, GABA and glutamate, suggesting that sNPF is a co-transmitter or local neuromodulator in ORNs and many interneurons. Interestingly, sNPF is coexpressed both with presumed excitatory and inhibitory neurotransmitters. A few sNPF expressing neurons in the brain colocalize the peptide corazonin and a pair of dorsal neurons in the first abdominal neuromere coexpresses sNPF and insulin-like peptide 7 (ILP7).
CONCLUSION:It is likely that sNPF has multiple functions as neurohormone as well as local neuromodulator/co-transmitter in various CNS circuits, including olfactory circuits both at the level of the first synapse and at the mushroom body output level. Some of the sNPF immunoreactive axons terminate in close proximity to neurosecretory cells producing ILPs and adipokinetic hormone, indicating that sNPF also might regulate hormone production or release.
|MeSH||Acetylcholine / metabolism Animals Axons / metabolism Basic Helix-Loop-Helix Transcription Factors / genetics Basic Helix-Loop-Helix Transcription Factors / metabolism Cell Adhesion Molecules, Neuronal / genetics Cell Adhesion Molecules, Neuronal / metabolism Central Nervous System / metabolism* Drosophila Proteins / genetics Drosophila Proteins / metabolism Drosophila melanogaster Gene Expression Glutamic Acid / metabolism Immunohistochemistry In Situ Hybridization Interneurons / metabolism* Larva / genetics Larva / metabolism Mass Spectrometry Mushroom Bodies / metabolism Neurons / metabolism* Neuropeptides / genetics Neuropeptides / metabolism* Neurotransmitter Agents / genetics Neurotransmitter Agents / metabolism Olfactory Receptor Neurons / metabolism Time Factors gamma-Aminobutyric Acid / metabolism|
|Drosophila||snpf-Gal4 (NP6301 DGRC#113901)|