SPATIAL AND TEMPORAL ANALYSIS OF THE DROSOPHILA FMRFAMIDE NEUROPEPTIDE GENE-PRODUCT SDNFMRFAMIDE - EVIDENCE FOR A RESTRICTED EXPRESSION PATTERN

The expression of SDNFMRFamide, one of five different FMRFamide-contai ning peptides encoded by the Drosophila melanogaster FMRFamide gene, h as been determined. To study expression, we generated antisera to the N-terminus of SDNFMRFamide to avoid cross-reactivity with FMRFamide-co ntaining peptides. The antisera were purified and the specificity char acterized. SDNFMRFamide immunoreactive material is present in the cent ral nervous system throughout development. Immunoreactivity is first o bserved in embryonic neural tissue in a cluster of cells in the subeso phageal ganglion and immunoreactive fibers projecting from these cells to the brain and ventral ganglion. This pattern of expression is also observed in neural tissue dissected from larva, pupa, and adult. Doub le-labelling experiments indicate that cells recognized by SDNFM-antis era are also stained with FMRFamide antisera. Based on position, SDNFM RFamide immunoreactive material is expressed in a limited number of ce lls that contain the FMRFamide polypeptide precursor. This finding sug gests that the Drosophila FMRFamide precursor undergoes differential p ost-translational processing.