Figure 7.

Spinal neurons loaded with rhodamine-2 AM dye are definitively identified as MNs. A, The EGFP-expressing parga^mn2Et enhancer trap line (A, green) was labeled with antibodies to choline acetyl transferase (ChAT; A′, magenta). Colabeling (A′′) of EGFP with ChAT antibodies indicated that EGFP expression in the parga^mn2Et line is a marker of spinal MNs. White arrowheads indicate ChAT-positive cells that do not contain EGFP (non-MNs). B, Live parga^mn2Et larvae were anesthetized, skinned, and incubated in rhodamine-2 AM dye (Rhod-2, AM). EGFP expression (B, green) and Rhod-2, AM labeling (B′, magenta), showed that Rhod-2, AM specifically labeled all MNs (B′′). White arrowheads indicate two Rhod-2, AM-labeled cells that did not contain EGFP. Scale bar: 20 μm.