Figure 2.

Projection Neurons Relay Information from Individual VP Glomeruli to Higher Brain Centers

(A) Frontal view of all VP PNs, color-coded by primary glomerulus.

(B) Summary diagram of the tracts and neuroblast lineages of VP PNs.

(C) Summary diagram of the target brain neuropils of VP PNs, color-coded to correspond with all other figure panels. AL: antennal lobe; AMMC: antennal mechanosensory and motor center; CA: mushroom body calyx; ICL: inferior clamp; IPS: inferior posterior slope; lACA: lateral accessory calyx; LH: lateral horn; PLP: posterior lateral protocerebrum; PVLP: posterior ventral protocerebrum; SCL: superior clamp; SEZ: subesophageal zone; SLP: superior lateral protocerebrum; SMP: superior medial protocerebrum; WED: wedge.

(D) Morphological hierarchical clustering based on NBLAST scores for VP PNs in each hemisphere, cut at height 0.8 (dashed line), which groups the PNs by type. Dark cyan: RHS. Dark red: LHS. Square brackets: unique VP PNs matched across hemispheres. For each type with multiple examples, numbers (#1, etc.) reflect order of appearance in the SKID_R or SKID_L columns in Table 1.

(E–Q’) Frontal views of reconstructions (black) of candidate thermo- and hygrosensory PNs that innervate one primary glomerulus (color-coded as in Figures 1B and 1B’, non-VP glomeruli in gray). Presynaptic sites in red and postsynaptic sites in cyan. Neuropils color-coded as in (C). Asterisks: primarily olfactory PNs; black outline: candidate novel thermosensory PNs; dashed outline: PNs previously described but not recognized as VP or thermosensory. (E) VP1d il2PN, (E') VP1d il2PN, (F) VP1l+ lvPN1#1, (G) VP2+ adPN, (H) VP3+ l2PN1#1, (I) VP4 vPN, (J) VP4+ vPN, (J') VP4+ vPN, (K) VP5 l2PN, (L) VP1m l2PN, (M) VP2 l2PN, (N) VC5+ adPN*, (O) VP2 adPN, (P) VP3 vPN, (Q) VP3+ l2PN2#1, (Q') VP3+ l2PN2#1.