sNPF is expressed in the embryo in the midline in VUM interneuron 2 (called iVUM5 in the paper) of the labial segment and segments T1-A7.

In situ labelling closely approximates that of antisera labelling in both adults and larvae. At the larval stage approximately 35 neurons per hemisphere, other than the Kenyon cells, are positive for sNPF mRNA. These cells are located dorsally and ventrally and include three strongly labelled neurons with large cell bodies that are probably neurosecretory cells. In each of the thoracic and abdominal neuromeres of the larval ventral nerve cord, three to four lateral cell bodies and one dorso-medial cell body express sNPF transcript. In abdominal neuromeres A7 and A8 there are additional labelled cell bodies with large diameters, and a pair of large dorso-medially located cell bodies expressing sNPF transcript are found in abdominal segment A1. In adults, expression of sNPF transcript is seen in approximately 280 neuronal cell bodies other than the Kenyon cells. The approximately 28 neurons distributed in the adult subesophageal ganglion are located in three bilateral clusters: one cluster close to the esophageal foramen; another ventrolateral in the ganglion; and a third cluster dorsolateral in the ganglion. At the base of the adult optic lobe there are clusters of about 50 small cell bodies distributed anteriorly and posteriorly. Several clusters of sNPF-XR expressing cells are located in the adult dorsal protocerebrum, mostly in the posterior with only approximately four cells located anteriorly.

Late embryonic expression of sPNF transcript is observed in the antennomaxillary sense organ, in the posterior of the brain hemispheres, in the fused ventral ganglion, and in bilaterally symmetrical pairs of cells along the ventral midline of the ventral ganglion. In the third instar larval central nervous system, expression is observed in the dorsal anterior region of the protocerebrum of the brain hemispheres, in cells of the subesophageal ganglion, along the ventral midline, and in the thoracic and abdominal segments of the ventral ganglion.

sNPF-protein is expressed in larval and adult Kenyon cells as well as in larval and adult lateral neurosecretory cells. Expression in Hugin neurons and antennal olfactory receptor neurons is only detected in adults.In addition, sNPF-protein is expressed in four cells of the hypocerebral ganglion express that project to the outermost layer of the proventriculus.

sNPF protein is expressed in a subset of neurons in the adult brain. Ten of these co-express mnb protein.

sNPF protein is expressed in 4 layers of the fan-shaped body. Co-localisation with ScerGAL4^GMR64H09 is observed in these regions.

sNPF colocalizes with ScerGAL4^ATP7.PB expressing peptidergic neurons in the hypocerebral ganglion.

sNPF protein is detected in dorsal and ventral layers of the fan-shaped body, which the authors identify as layers 1-2 and 6-7, respectively. The strongest staining is observed in layer 2. Co-localisation with ScerGAL4^Cha.7.4 is observed in the dorsal layers of the fan-shaped body and in a cluster of 6-8 neurons in the dorsoposterior protocerebrum. These latter neurons also express ScerGAL4^VGlut.PD.

sNPF peptides were detected in extracts from adult and larval midguts.

sNPF protein is expressed in distinct glomeruli in the adult antennal lobe. A subset of these is glomeruli is also labelled by ScerGAL4^Cha.7.4.

In the adult sNPF protein is expressed in three neurons of the LNd cluster. Two of these LNd neurons also express ScerGAL4^Mai179 and do not correspond to the LNd neurons labeled by ScerGAL4^npf.4.5 in males. In late third instar larva, sNPF protein is expressed in two s-LNv Pdf neurons. These two s-LNv Pdf neurons are also labeled by ScerGAL4^NP6301.

sNPF precursor and sNPF1 peptide are co-localized in the same neurons in the third instar larval brain. sNPF is detected in large numbers of cell bodies and axons within the brain, ventral ganglion, and ring gland. In the brain, it is detected in the neurons, Kenyon cells, and mushroom body. In the ring gland, corpora cardiaca region, strong staining is observed in axonal projections from neurons adjacent to insulin-producing cells.

Strong sNPF staining is seen in cell bodies in the hypocerebral ganglion with axons running over the proventriculus and the first part of the anterior midgut. Staining is also observed in the anterior midgut and in the posterior midgut immediately after the iron cells.

In adult mushroom bodies, sNPF protein is strongly expressed at the end of the alpha lobe, and in the beta and gamma lobes, and heel. Expression is absent from the core stratum of the alpha and beta lobes, and in the alpha' and beta' lobes. In the larva, strong staining is detected in the dorsal tips of the vertical lobes and in the median portions of the medial lobe. Expression is absent from the core of the peduncle, vertical and medial lobes.

Antisera labelling closely approximates that of in situ labelling in both adults and larvae. sNPF protein appears to be expressed in most of the approximately 600 larval Kenyon cells, and in 190-200 cells of the larval central nervous system, approximately 70 of which are in the brain (including the subesophageal ganglion) and a minimum of 120 in the thoracic and abdominal neuromeres. Three pairs of intensely immunolabelled cells (referred to as LNCs) located dorsally in the protocerebrum are probably neurosecretory cells of the pars lateralis and have axons terminating in the ring gland and anterior aorta. Processes of sNPF immunopositive larval cells are seen in neuropils of the protocerebrum, deutocerebrum, subesophageal ganglion, and most densely in the lobes of the mushroom body. Further processes are seen in the larval optic center, non-glomerular neuropils surrounding the mushroom body lobes, and the pars intercerebralis and lateralis. In the abdominal and thoracic neuromeres of the larval ventral nerve cord, sNPF immunopositive cells are located dorsally, ventrally and laterally. In larval abdominal neuromeres A7 and A8 there are additional immunopositive cell bodies with large diameters, and a pair of large dorso-medially located cell bodies expressing sNPF-XP are found in abdominal segment A1. Two bundles of sNPF immunopositive fibres are found in the ventral ganglia associated with the dors-median and ventro-median tracts. Expression was also seen in two layers of the fan shaped body of the central complex, and in the basal portion of the medulla. Expression within the antennal lobe is located within the olfactory receptor neurons, as determined by coexpression of ScerGAL4^Cha.7.4.

sNPF peptide is found in neurons in the dorsal anterior of the larval prototcerebrum, and in six projecting axons of the thoracic ventral ganglion, and in axons of the descending connectives in the abdominal ventral ganglion. In the adult, sNPF peptide is found in the medulla of the optic lobe and in the calyx of the mushroom body.