Comment: Authors call this '1 adPN'.
Drives expression in projection neurons, particularly antennal lobe projection neurons.
Scer\GAL4GH146 is expressed in several cells of the adult brain, including a subset of antennal lobe projection neurons and in the mushroom body anterior paired lateral neurons.
Scer\GAL4GH146 labels a subset of projection neurons and the mushroom body anterior paired lateral cell. Co-expression of Scer\GAL4GH146 with a presynaptic marker preferentially labels the presynaptic terminals of the mushroom body anterior paired medial cell throughout the mushroom body with stronger expression in the alpha'/beta' lobes.
Scer\GAL4GH146 labels the antennal lobe projection neurons. Co-expression with a postsynaptic marker reveals that in the mushroom body calyx, these sites are juxtaposed to the presynapses of the Kenyon cells.
Labelling is observed in olfactory projection neurons.
Scer\GAL4GH146 is expressed in an average of 73, 193 and 49 cells of the adPN, lPN and vPN lineages, respectively.
Although most projection neurons are not GABA-immunopositive, approximately 6 Scer\GAL4GH146 positive neurons, located ventral and slightly lateral to the antennal lobes, are GABA-positive.
Scer\GAL4GH146 is expressed by approximately 90 projection neurons that innervate approximately 40 of the roughly 50 adult antennal lobe glomeruli. Scer\GAL4GH146 is expressed in presumptive larval projection neurons that send neurites that appear to innervate the mushroom body calyx and the larval equivalent of the adult lateral horn.
Scer\GAL4GH146 is estimated to express in about two thirds of the antennal lobe projection neurons.
Use of UAS-GFP with nuclear localization signal allows visualization of cell bodies. In the adult brain, expression observed in clusters of cells (identified as projection neurons) surrounding the antennal lobe in 3 anatomically distinct groups: ~41 cells dorsal-anterior, ~34 cells lateral and ~7 cells ventral. In addition, expression observed in small number of cells that are not projection neurons: 6 cells posterior and lateral to the protocerebrum and 3 cells ventral to the subesophageal ganglion.
Use of UAS-CD8-GFP allows visualization of axons and dendrites. In the adult brain, the 'projection neurons' (relay interneurons) extend dendrites to specific glomeruli in the antennal lobe; the majority send dendrites to only one glomerulus. Projection neurons that innervate the same glomerulus exhibit similar patterns of axon arborization. The majority extend axons through the iACT and synapse both in the calyx of the mushroom body and the lateral protocerebrum; a small number extend axons through the mACT or the oACT, bypass the mushroom body, and connect to the protocerebrum.
The majority of axons from neurons in which Scer\GAL4GH146 expresses project through the inner antenno-cerebral tract and synapse in both the calyx of the mushroom body and the lateral cerebrum. It is expressed in at least 4 neurons that send axons through the middle antenno-cerebral tract and a single neuron projecting through the outer antenno-cerebral tract. These latter two tracts bypass the mushroom body and connect directly with the protocerebrum.
Scer\GAL4GH146 is expressed in some subset of adult antennal lobe projection neurons of the ventral, antero-dorsal and ventral antennal lobe neuroblast lineages. Because of this expression it specifically marks a number of adult antennal lobe glomeruli, the inner and medial antenno-cerebral tracts and parts of the mushroom body calyx and lateral horn.
In adult brain, expressed in lateral protocerebrum (LPR), relay interneurons, inner and median antenno-cerebral tracts (iACT, mACT), and calyx of mushroom body; also in 'descending interneurons' ventral to the LPR, with processes extending into the iACT. In pupal brain, expression first observed 24h APF.