AMMC-B1 [FBbt_00110120]

AMMC-B1

ID: FBbt_00110120

Projection neuron whose cell body is located at the lateral side of the posterior antennal lobe (Matsuo et al., 2016). The primary neurite projects medially and makes a steep turn ventrally to form two branches at the dorsal side of the antennal mechanosensory and motor center (AMMC) (Matsuo et al., 2016). The ventrolateral branch forms postsynaptic terminals in the AMMC zone B (Matsuo et al., 2016). The dorsal branch bifurcates in the ipsilateral epaulette, projecting above the esophagus, to form presynaptic terminals both the ipsilateral and the contralateral wedge (Matsuo et al., 2016). These neurons are activated by an acoustic stimuli and two subtypes can be recognized, AMMC-B1a and AMMC-B1b, which differ with respect to JO neuron connectivity and auditory response. The former responds to 100 Hz stimuli and the latter responds to 100 and 300 Hz stimuli (Lai et al., 2012). They preferentially respond to male pulse, rather than sine, song (Baker et al., 2022). There are around 10 of these neurons per hemisphere and they receive substantial synaptic input from zone B Johnston organ neurons (Kim et al., 2020). It is part of the olfactory lPN (ALl1) lineage (Vaughan et al., 2014).

Auditory function was determined measuring GCaMP activation in these cells in response to an acoustic stimuli. Subsets of AMMC-B1 neurons were labelled with the drivers: E0564-GAL4, E0583-GAL4, VT27938-GAL4 and VT19992-GAL4 (these lines label AMMC-B1a neurons); VT10277-GAL4, VT45599-GAL4, VT20611-GAL4, VT26006-GAL4 and GH86-GAL4 (FBti0009836) (these lines label AMMC-B1b neurons); and VT30609-GAL4 (labels AMMC-B1 and AMMC-A2 neurons). Single cell imaging with various drivers showed that AMMC-B1 neurons are isomorphic. Presence of pre- and postsynaptic sites was determined by immunoreactivity to Dscam- and synaptotagmin-GFP localization, respectively (Lai et al., 2012). Image registration analysis supports an overlap between the dendrites of vPN1 neurons and axons terminals of AMMC-B1 neurons in the wedge (Zhou et al., 2015). Some AMMC B1 neurons also arborize in the ipsilateral gnathal ganglion (Matsuo et al., 2016).