CELLULAR EXPRESSION OF THE DROSOPHILA-MELANOGASTER FMRFAMIDE NEUROPEPTIDE GENE-PRODUCT DPKQDFMRFAMIDE - EVIDENCE FOR DIFFERENTIAL PROCESSING OF THE FMRFAMIDE POLYPEPTIDE PRECURSOR

DPKQDFMRFamide is one of five different FMRFamide-containing peptides encoded in the Drosophila FMRFamide gene. To study the cellular expres sion of DPKQDFMRFamide, we have generated antisera to DPKQD, the N-ter minal sequence of the peptide, to avoid crossreactivity with other -FM RFamide-containing peptides. The antisera were purified and the specif icity characterized. DPKQDFMRFamide immunoreactive material is first o bserved in the embryonic central nervous system (CNS) in one cell of t he subesophageal ganglion and one cell in each of the three thoracic g anglia. This pattern of expression is observed in larval, pupal, and a dult neural tissue, albeit with increased signal intensity. In larva, pupa, and adult, additional cells in the superior protocerebrum, a tho racic ganglion, and an abdominal ganglion express DPKQDFMRFamide immun oreactive material. Immunoreactivity is observed in a cell in the late ral protocerebrum of pupa and adult and cells in the optic lobe of adu lt. No immunoreactive material was observed in gut tissue. DPKQDFMRFam ide antisera stain a subset of cells previously identified by in situ hybridization and immunocytochemistry to express the FMRFamide transcr ipt and polypeptide precursor. These data suggest that the Drosophila FMRFamide polypeptide precursor undergoes differential processing to p roduce DPKQDFMRFamide immunoreactive material in a limited number of c ells expressing the FMRFamide precursor.