Fig. 3. Dendritic arborization patterns of projection neurons (PNs) in the macroglomerular complex (MGC) of O. nubilalis. PN (green) in a red -synapsin-labeled background. Left panel: some confocal sections with part of the neuron visible. Note that to visualize large parts of the neuron several confocal sections were overlayed, which blurs glomerular delineations. Right panel: three-dimensional reconstruction of the two large MGC glomeruli (lateral, pink; medial, blue) and axonal projection of the olfactory receptor neuron (ORN; green). For clarity, the glomerulus receiving axonal input is also shown excised from the MGC. (A) The MGC of a Z-strain male displaying a Z11-14:OAc-specific PN staining with exclusive arborizations in the medial glomerulus. (B) The MGC of a Z-strain male displaying dendrites of E11-14:OAc-specific PNs only arborizing in the lateral glomerulus. (C) The MGC of an E-strain male displaying an E11-14:OAc-specific PN staining. E11-14:OAc-specific PNs arborized exclusively in the larger, medial MGC compartment. (D) As in C but now displaying a Z11-14:OAc-specific PN staining. In the E-strain, Z11-14:OAc-specific PN arborizations were restricted to the lateral MGC compartment. (E) A blend-specific PN, responding more strongly to a blend of Z11- or E11-14:OAc than the sum of the responses to the components separately, typically arborized in both large MGC glomeruli. (F) Typical responses of Z11- and E11-14:OAc-specific PN in the Z-strain. Scale bars, 50 µm.