Tm1 [FBbt_00003789]

Tm1

ID: FBbt_00003789

Transmedullary narrow field neuron that terminates in lobula layer 1 with a bleb-type terminal arborization and that has fine arborizations in medulla layer M2 and bleb-type arborizations in M3 and M9 (Fischbach and Dittrich, 1989; Takemura et al., 2011). In the medulla, it receives strong synaptic input from lamina monopolar neuron L2 (Takemura et al., 2011; Takemura et al., 2013). It outputs onto T5 neurons (Shinomiya et al., 2019). It is a cholinergic neuron (Varija Raghu et al., 2011; Shinomiya et al., 2014). There is usually one of these cells per optic column (Nern et al., 2025).

The neurotransmitter was assessed by co-labelling cells with a P{Cha-GAL4.7.4} driver (FBtp0014830) and an anti-ChAT antibody (Varija Raghu et al., 2011; Shinomiya et al., 2014). Pre- versus postsynaptic innervation judged by scoring of terminal morphology from figures in Fischbach and Dittrich (1989) as assessed by FlyBrain Neuron DB. Connectivity in the medulla was extrapolated from serial EM of 3 columns from a single sample (Takemura et al., 2008) or from 7 columns (Takemura et al., 2013). Connectivity in the lobula was assessed by serial section electron microscopy of a single column (Shinomiya et al., 2014). Connectivity in the entire optic lobe was also assessed by EM (Shinomiya et al., 2019).