title: Identification and partial characterization of the enzyme of omega: one of five putative DPP IV genes in Drosophila melanogaster.
abstract: The omega (ome) gene product is a modifier of larval cuticle protein 5 and its alleles (and duplicates) in the third instar of Drosophila melanogaster. Using deletion mapping the locus mapped to 70F-71A on the left arm of chromosome 3. A homozygote null mutant (ome 1) shows a pleiotropic phenotype that affected the size, developmental time of the flies, and the fertility (or perhaps the behavior) of homozygous mutant males. The omega gene was verified as producing a dipeptidyl peptidase IV (DPPIV) by genetic analysis, substrate specificity and pH optimum. The identity of the gene was confirmed as CG32145 (cytology 70F4) in the Celera Database (Berkeley Drosophila Genome Project), which is consistent with its deletion map position. The genomic structure of the gene is described and the decrease in DPPIV activity in the mutant ome1 is shown to be due to the gene CG32145 (omega). The D. melanogaster omega DPPIV enzyme was partially purified and characterized. The exons of the ome1 mutant were sequenced and a base substitution mutation in exon 4 was identified that would yield a truncated protein caused by a stop codon. A preliminary study of the compartmentalization of the omega DPPIV enzyme in several organs is also reported.
authors.affiliation: University of San Francisco, Department of Biology, 2130 Fulton St., San Francisco, CA 94117-1080, USA.
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Chihara
authors.forename: Chunyan
authors.initials: C
authors.lastname: Song
authors.forename: Greg
authors.initials: G
authors.lastname: LaMonte
authors.forename: Kristina
authors.initials: K
authors.lastname: Fetalvero
authors.forename: Kristy
authors.initials: K
authors.lastname: Hinchman
authors.forename: Helen
authors.initials: H
authors.lastname: Phan
authors.forename: Mario
authors.initials: M
authors.lastname: Pineda
authors.forename: Kelly
authors.initials: K
authors.lastname: Robinson
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Schneider
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism; D002462:Cell Membrane; D002874:Chromosome Mapping; D003600:Cytosol / Q000378:metabolism; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics / Q000378:metabolism*; D054873:Dipeptidyl-Peptidase IV Inhibitors; D029721:Drosophila Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000378:metabolism; D008297:Male; D009154:Mutation; D010053:Ovary / Q000378:metabolism; D010802:Phylogeny; D013737:Testis / Q000378:metabolism
chemical_list: D054873:Dipeptidyl-Peptidase IV Inhibitors; D029721:Drosophila Proteins; D018819:Dipeptidyl Peptidase 4; C516252:ome protein, Drosophila