Fig. 5

Retrograde viral Cre and germline FLP mediated expression of dual recombinases for tricistronic FP expression on RR5 background. A RR5; DBH^p2aFLPo mice were injected with CAV2-Cre virus into the basolateral amygdala. All DBH noradrenergic neurons express FLP, but only those noradrenergic neurons projecting to the injected amygdala will also express Cre. Marked double Cre/FLP-positive cells will express H2B-TagBFP highlighting the nucleus in blue, sfGFP filling the cell including the axon, and synaptophysin-tdTomato labeling presynaptic contacts. BLA: Basolateral amygdala. DG: Dentate gyrus. DR: Dorsal raphé. LC: Locus coeruleus. OB: Olfactory bulb. RtTg: Reticulotegmental pontine nucleus. DBH-positive neurons that project to the amygdala arise primarily from the ipsilateral locus coeruleus (B–E) with some sparse labeling in the contralateral locus coeruleus (F–I). Red puncta overlapping with green but lacking blue marked nuclei (indicative of projections from the marked population) can be seen in a variety of mid- and forebrain areas, including the injected amygdala (J–M), the raphé nucleus (N–Q), reticulotegmental pontine nuclei (R–U), dentate gyrus (V–Y), and olfactory bulb (Z–CC)