Abstract
The Drosophila melanogaster Gad gene maps to region 64A3-5 of chromosome 3L and encodes glutamic acid decarboxylase (GAD), the rate-limiting enzyme for the synthesis of the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Because this neurotransmitter has been implicated in developmental functions, we have begun to study the role of GABA synthesis during Drosophila embryogenesis. We show that Gad mRNA is expressed in a widespread pattern within the embryonic nervous system. Similarly, GAD-immunoreactive protein is present during embryogenesis. These results prompted us to screen for embryonic lethal mutations that affect GAD activity. The chromosomal region to which Gad maps, however, has not been subjected to an extensive mutational analysis, even though it contains several genes encoding important neurobiological, developmental, or cellular functions. Therefore, we have initially generated both chromosomal rearangements and point mutations that map to the Drosophila 64AB interval. Altogether, a total of 33 rearrangements and putative point mutations were identified within region 64A3-5 to 64B12. Genetic complementation analysis suggests that this cytogenetic interval contains a minimum of 19 essential genes. Within our collection of lethal mutations are several chromosomal rearrangements, two of which are in the vicinity of the Gad locus. One of these rearrangements, Df(3L)C175, is a small deletion that removes the Gad locus and at least two essential genes; the second, T(2;3)F10, is a reciprocal translocation involving the second and third chromosomes with a break within region 64A3-5. Both of these rearrangements are associated with embryonic lethality and decreased GAD enzymatic activity.
Similar content being viewed by others
References
Anthony NM, Harrison JB, Sattelle DB (1993) GABA receptor molecules of insects. In: Pichon Y (ed) Comparative Molecular Neurobiology. Birkhauser Verlag, Basel, Switzerland, pp 172–209
Baker WK (1968) Position-effect variegation. Adv Genet 14:133–169
Buchner E, Bader R, Buchner S, Cox J, Emson PC, Flory E, Heizmann CW, Hemm S, Hofbauer A, Oertel WH (1988) Cell-specific immuno-probes for the brain of normal and mutant Drosophila melanogaster I. Wild-type visual system. Cell Tissue Res 253:357–370
Culiat CT, Stubbs L, Nicholls RD, Montgomery CS, Russell LB, Johnson DK, Rinchik EM (1993) Concordance between isolated cleft palate in mice and alterations within a region including the gene encoding the β3 subunit of the type A γ-aminobutyric acid receptor. Proc Natl Acad Sci USA 90:5105–5109
Engels WR, Preston CR, Thompson P, Eggleston WB (1986) In situ hybridization to Drosophila salivary chromosomes with biotinylated DNA probes and alkaline phosphatase. Focus 8:6–8
Erlander MG, Tobin AJ (1991) The structural and functional heterogeneity of glutamic acid decarboxylase. Neurochem Res 16:215–226
Hoffman-Falk H, Einat P, Shilo B-Z (1983) Drosophila melanogaster DNA clones homologous to vertebrate oncogenes: evidence for a common ancestor to the src and abl cellular genes. Cell 32:589–598
Jackson FR, Wilson SD, Hall LM (1986) The tip-E mutation of Drosophila decreases saxitoxin binding and interacts with other mutations affecting nerve membrane excitability. J Neurogenet 3:1–17
Jackson FR, Newby LM, Kulkarni SJ (1990) Drosophila GABAergic systems: Sequence and expression of glutamic acid decarboxylase. J Neurochem 54:1068–1078
Lauder JM (1988) Neurotransmitters As Morphogens. Prog Brain Res 73:365–387
Lauder JM, Krebs H (1986) Do neurotransmitters, neurohumors, and hormones specify critical periods? In: Greenough WT, Juraska JM (ed) Developmental Neuropsychobiology. Academic Press, New York, pp 119–174
Lindsley DL, Zimm G (1992) The genome of Drosophila melanogaster. Academic Press, New York
Lipton SA, Kater SB (1989) Neurotransmitter regulation of neuronal outgrowth, plasticity, and survival. Trends Neurosci 12:265–270
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193:265–275
Martin DL, Rimvall K (1993) Regulation of γ-aminobutyric acid synthesis in the brain. J Neurochem 60:395–407
Mattson MP, Kater SB (1989) Excitatory and inhibitory neurotransmitters in the generation and degeneration of hippocampal neuroarchitecture. Brain Res 478:337–348
Mozer B, Marlor R, Parkhurst S, Corces V (1985) Characterization and developmental expression of a Drosophila ras oncogene. Mol Cell Biol 5:885–889
Nakatsu Y, Tyndale RF, DeLorey TM, Durham-Pierre D, Gardner JM, McDanel HJ, Nguyen Q, Wagstaff J, Lalande M, Sikela JM, Olsen RW, Tobin AJ, Brilliant MH (1993) A cluster of three GABAA receptor subunit genes is deleted in a neurological mutant of the mouse p locus. Nature 364:448–450
Newby LM, Jackson FR (1993) A new biological rhythm mutant of Drosophila melanogaster that identifies a gene with an essential embryonic function. Genetics 135:1077–1090
Newby LM, White L, Dibartolomeis SM, Walker BJ, Dowse HB, Ringo JM, Khuda N, Jackson FR (1991) Mutational analysis of the Drosophila miniature-dusky (m-dy) locus: Effects on cell size and circadian rhythms. Genetics 128:571–582
Newby LM, Kulkarni SJ, Jackson FR (1993) Transcriptional organization of a Drosophila glutamic acid decarboxylase gene. J Neurochem 60:982–989
Oertel WH, Schmechel DE, Tappaz ML, Kopin IJ (1981) Production of a specific antiserum to rat brain glutamic acid decarboxylase by injection of an antigen-antibody complex. Neuroscience 6:2689–2700
Olsen OA, Green MM (1982) The mutagenic effects of diepoxybutane in wild-type and mutagen-sensitive mutants of Drosophila melanogaster. Mutat Res 92:107–115
Redburn DA, Schousboe A (1987) Neurotrophic activity of GABA during development. Alan R. Liss, New York
Schaffer MH, Noyes BE, Slaughter CA, Thorne GC, Gaskell SJ (1990) The fruitfly Drosophila melanogaster contains a novel charged adipokinetic-hormone-family peptide. Biochem J 269:315–320
Shukla PT, Auerbach C (1980) Genetic tests for the detection of chemically induced small deletions in Drosophila chromosomes. Mutat Res 72:231–243
Sorsa V (1988) Chromosome Maps of Drosophila, vol. II. CRC Press, Boca Raton
Spoerri PE (1988) Neurotrophic effects of GABA in cultures of embryonic chick brain and retina. Synapse 2:11–22
Tautz D, Pfeifle CA (1989) A non-radioactive in situ hybridization method for the localization of specific RNAs in Drosophila embryos reveals translational control of the segmentation gene hunchback. Chromosoma 98:81–85
Wadsworth SC, Rosenthal LS, Kammermeyer KL, Potter MB, Nelson DJ (1988) Expression of a Drosophila melanogaster acetylcholine receptor-related gene in the central nervous system. Mol Cell Biol 8:778–785
Wohlwill AD, Bonner JJ (1991) Genetic analysis of chromosome region 63 of Drosophila melanogaster. Genetics 128:763–775
Author information
Authors and Affiliations
Additional information
Communicated by M. Ashburner
Rights and permissions
About this article
Cite this article
Kulkarni, S.J., Newby, L.M. & Rob Jackson, F. Drosophila GABAergic systems II. Mutational analysis of chromosomal segment 64AB, a region containing the glutamic acid decarboxylase gene. Molec. Gen. Genet. 243, 555–564 (1994). https://doi.org/10.1007/BF00284204
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00284204