title: Eukaryotic operon-like transcription of functionally related genes in Drosophila.
abstract: Complex biological processes require coordinated function of many genes. One evolutionary solution to the problem of coordinately expressing functionally related genes in bacteria and nematodes is organization of genes in operons. Surprisingly, eukaryotic operons are considered rare outside the nematode lineage. In Drosophila melanogaster, we found lounge lizard (llz), which encodes a degenerin/ENaC cation channel, cotranscribed with CheB42a, a nonhomologous gene of unknown function residing <100 bp upstream. These two genes were transcribed from a single promoter as one primary transcript and were processed posttranscriptionally to generate individual mRNAs. The mechanism did not involve alternative splicing, and it differed from the trans splicing used in nematode operons. Both genes were expressed in the same tissues, and previous work suggested that both may be involved in courtship behavior. A bioinformatic approach identified numerous additional loci as potential Drosophila operons. These data reveal eukaryotic operon-like transcription of functionally related genes in Drosophila. The results also suggest that operon-based transcription may be more common in eukaryotes than previously appreciated.
authors.affiliation: Howard Hughes Medical Institute, and Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine Center for Bioinformatics and Computational Biology, University of Iowa, Iowa City, IA 52242, USA.
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Ben-Shahar
authors.forename: Kishore
authors.initials: K
authors.lastname: Nannapaneni
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Casavant
authors.forename: Todd E
authors.initials: TE
authors.lastname: Scheetz
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Welsh
mesh_terms: D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis; D016601:RNA-Binding Proteins / Q000235:genetics*; D017412:Ribonucleoprotein, U1 Small Nuclear / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: C469827:CheB42a protein, Drosophila; D029721:Drosophila Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D017412:Ribonucleoprotein, U1 Small Nuclear; C089969:snf protein, Drosophila