We also detected PRT expression in the peduncle, formed by KC axons before they branch into the lobes (Figures 3D–3F). PRT was not distributed uniformly throughout the peduncle, and a portion of the core was weakly labeled (Figures 3D–3F; data not shown). This pattern suggests that PRT may not be expressed in all KCs, although further experiments will be needed to confirm this. Several additional cell bodies near the MBs express PRT (Figures 3A–3C and 3F), as well as one cluster of two to three cells in the subesophageal ganglion that projects medially Bortezomib toward

the esophogeal foramen (arrows, Figure 3F). During metamorphosis there is also extensive development of the central complex, a midline structure just posterior to the MB medial lobes involved in motor activity (Strauss, 2002) and visual memory (Liu et al., 2006). PRT labeling of the adult brain revealed that it is expressed in components of the CCX, including the neuropil of the ellipsoid and fan-shaped bodies (Figures 3G and 3H). We also detected PRT expression in two bilaterally symmetric clusters of two and three cells, each near the medial aspect of the optic lobe, that project outward toward the medulla (asterisks, Figure 3I). The cartoon in Figure 3J summarizes the PRT expressing cells in the adult. Pifithrin-�� mw Other than the KCs, there are approximately 56 labeled

cell bodies. For comparison, the adult brain contains approximately 300 dopaminergic and 106 serotonergic cells (Monastirioti, 1999). To complete our survey of the adult central nervous system, we also labeled the thoracic ganglion and found three clusters with two to four cells each that lie near the ventral midline ALOX15 (Figures 3K–3M). This expression pattern was not sexually dimorphic (Figures 3L and 3M). To investigate the function of PRT, we generated a mutant

fly. A survey of the public database revealed a previously generated line with a SUPor-P element inserted into the 5′ untranslated region (UTR) of prt ( Figure 4A). Line KG07780 was obtained from the Bloomington Stock Center (Indiana University), and we confirmed that the SUPor-P element was located 118 bp upstream of the predicted initiating methionine (data not shown). We used imprecise excision to generate a prt mutation. Lines were screened by PCR, with primers flanking the P element insertion. In wild-type Canton-S (CS) flies, we detected a major product that migrated at 1.2 kb, consistent with the size predicted by the primary sequence ( Figure 4B). In one line, the major band migrated at 400 bp, consistent with an 850 bp deletion ( Figure 4B). We designated this allele prt1. We immunolabeled adult brains to determine whether prt1 mutants produce any residual protein, and we failed to detect any labeling of the MBs or elsewhere ( Figure 4C). These data confirm the specificity of the antiserum to PRT.