Genetic and molecular identification of a Drosophila histidine decarboxylase gene required in photoreceptor transmitter synthesis

• Published in: The EMBO journal Vol. 12; no. 3; pp. 911 - 919
• Main Authors: Burg, M.G, Sarthy, P.V, Koliantz, G, Pak, W.L
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01.03.1993
• Subjects: Amino Acid Sequence; amino acid sequences; Animals; Base Sequence; Biological and medical sciences; brain; carboxy-lyases; complementary DNA; compound eyes; DNA; Drosophila; Drosophila melanogaster; Fundamental and applied biological sciences. Psychology; ganglia; genbank/x70644; Gene Expression; Genes; Genes. Genome; hdc gene; Histidine Decarboxylase - genetics; Humans; messenger RNA; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; mutagenesis; mutants; Neurotransmitter Agents - biosynthesis; nucleotide sequences; Photoreceptor Cells - metabolism; photoreceptors; RNA, Messenger - genetics; Sequence Homology, Amino Acid; structural genes; Tissue Distribution; Transformation, Genetic; Nucleotide sequence; Enzyme; Insecta; Drosophila; Photoreceptor; Gene expression; Histidine decarboxylase; Drosophilidae; Phenotype; Complementary DNA; Gene; Synaptic transmission; Arthropoda; Mutation; Invertebrata; Diptera; Aminoacid sequence
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1993.tb05732.x

Drosophila mutants of a single complementation group with defective on-/off-transients of the electroretinogram (ERG) were found to be deficient in synthesis of the photoreceptor transmitter, histamine, in a gene-dosage dependent manner, suggesting that the gene identified by the mutants (hdc) might be the structural gene for Drosophila histidine decarboxylase (HDC). A rat HDC cDNA was used to isolate a Drosophila homolog which shows approximately 60% sequence identity with mammalian HDCs over a region of 476 amino acids. In RNA blots, the Drosophila homolog detects four transcripts that are expressed primarily in the eye and are severely reduced in hdc mutants. The cloned Drosophila cDNA hybridizes to the 46F region of the chromosome, to which hdc mutations have been mapped, and rescues the hdc mutant phenotype in transgenic flies generated by P element-mediated germline transformation. The results thus show that the Drosophila homolog corresponds to the histidine decarboxylase gene, identified by the hdc mutants, and that mutations in the gene disrupt photoreceptor synaptic transmission.