ExFl2 [FBbt_00007535]

ExFl2

ID: FBbt_00007535

GABAergic extrinsic lateral fan-shaped body tangential neuron that projects dorso-anteriorly to the posterior superior medial protocerebrum where it forms postsynaptic arborizations prior to forming presynaptic arborizations in the dorsal fan-shaped body (Young and Armstrong, 2010; Liu et al., 2016; Ni et al., 2019). The cell bodies of these neurons lie in a cluster lateral to the mushroom body calyx (Young and Armstrong, 2010). Arborization in the fan-shaped body spans a whole layer, but within that layer boundaries split the arborization into 16 segments (Young and Armstrong, 2010). These neurons express AstA-R1 and are activated downstream of glutamatergic AstA-expressing neurons, which synapse onto ExFl2 neurons in the superior medial protocerebrum, to increase daytime sleep; they also receive inhibitory input from dopaminergic neurons (Ni et al., 2019) and R2 ring neurons (Liu et al., 2016). They output onto and inhibit octopaminergic neurons in the fan-shaped body (Ni et al., 2019).

'dFB neuron' synonym added based on reference to FBrf0232501 in FBrf0241449 and paper seems to refer to a specific set rather than all neurons of dFB - https://orcid.org/0000-0002-1373-1705. Synapsing shown by GRASP and functional data (Ni et al., 2019). Dopaminergic input may be from PPL1-dFB, but not clear from Ni et al. (2019); identity of octopaminergic neurons also not clear. Fl6 mapped to ExFl2 as FlyBrain NDB (Fl6) and Young and Armstrong (2010) (ExFl2) both cite Hanesch et al. (1989) fig 22g.