In situ hybridization analysis of the FMRFamide neuropeptide gene in Drosophila. II. Constancy in the cellular pattern of expression during metamorphosis

Abstract

We have studied changes in the pattern of specific neuropeptide gene expression during the metamorphosis of the Drosophila nervous system. Prior to metamorphosis, the Drosophila FMRFamide gene is expressed exclusively within the central nervous system in a stereotyped pattern that comprises roughly 60 neurons (Schneider et al., '91). Using in situ hybridization, we found that the FMRFamide gene was continuously expressed throughout all stages examined: at each of 15 stages of adult development and through at least the first 10 days of adult life. There were no differences between the results observed with 2 exon-specific hybridization probes, thus indicating little if any alternative splicing during postembryonic development. Despite many changes in the positions of individual hybridization signals due to the large-scale reorganization of the nervous system, the continuous pattern of gene expression through adult development permitted many adult signals to be identified as larval signals. We concluded that the adult pattern of FMRFamide gene expression was largely derived from persistent larval neurons. Adult-specific hybridization signals in the brain and ventral ganglion were also detected and these corresponded to many of the approximately 40 adult-specific FMRFamide-immunoreactive neurons. One specific larval signal was lost during adult development and the intensities of other signals fluctuated in reproducible manners. These stereotyped differences in hybridization signal intensity resemble similar observations made in larval stages (Schneider et al., '91) and support the hypothesis that the steady-state levels of FMRFamide transcripts are differentially regulated among the diverse neurons that express the gene.

Chemical neuroanatomy of the Drosophila central complex: Distribution of multiple neuropeptides in relation to neurotransmitters

“…Here we used an antiserum directed to a precursor sequence derived from the Fmrf gene (pFMRFa; Chin et al, 1990), thus avoiding crossreactivity to other peptides with an RF-amide C-terminal (i.e., sNPF, NPF, sulfakinin, and myosuppressin). The distribution of dFMRFa has been described in detail in embryo and larvae using in situ hybridization, precursor, and region-specific antisera (O'Brien et al, 1991;Schneider et al, 1993b;Nichols, 2003). However, a description of FMRFa in the adult Drosophila central complex has not been published earlier.…”

Immunohistological localization of regulatory peptides in the midgut of the female mosquitoAedes aegypti

“…In situ hybridization with probes for the Drosophila FMRFamide gene did not yield a signal in the FMRFamide-immunoreactive cells in the midgut, suggesting that these peptides are not present there O'Brien et al 1991). It seems plausible, then, that the homologous gene in A. aegypti, if it exists, is similarly not expressed in the midgut.…”

“…In a competive ELISA for perisulfakinin set up according to the protocol described by Kingan (1989) the antiserum did not recognize RFamide, FMRFamide, or leucomyosuppressin in amounts of up to 10 nmol per well, while 100 fmol of perisulfakinin was easily detectable. Since such ELISA experiments are only indicative of the specificity of the antiserum in immunocytology, we also tested it in immunocytology on the central nervous system of prepupae of Drosophila melanogaster, the only insect species for which the differential localization of the the FMRFamides, leucomyosuppressins and sulfakinins has been determined O'Brien et al 1991;Nichols 1992, Tibbetts andNichols 1993).…”

Multiple Amidated Neuropeptides Are Required for Normal Circadian Locomotor Rhythms inDrosophila

“…It also highlights several organized neuropils, like the lobes of the Mushroom bodies and several sections of the Fan-Shaped body, and appears strongly in dorsal protocerebral neuropil and neuropil surrounding the esophageal foramen. 36Y-gal4-rescued animals (n ϭ 8) displayed PHM immunosignals in several identifiable peptidergic neurons [e.g., MP1 and MP2 neurons (O'Brien et al, 1991)] on a generally low background of staining (Figs. 1, 2).…”