title: Surprising gene expression patterns within and between PDF-containing circadian neurons in Drosophila.
abstract: To compare circadian gene expression within highly discrete neuronal populations, we separately purified and characterized two adjacent but distinct groups of Drosophila adult circadian neurons: the 8 small and 10 large PDF-expressing ventral lateral neurons (s-LNvs and l-LNvs, respectively). The s-LNvs are the principal circadian pacemaker cells, whereas recent evidence indicates that the l-LNvs are involved in sleep and light-mediated arousal. Although half of the l-LNv-enriched mRNA population, including core clock mRNAs, is shared between the l-LNvs and s-LNvs, the other half is l-LNv- and s-LNv-specific. The distribution of four specific mRNAs is consistent with prior characterization of the four encoded proteins, and therefore indicates successful purification of the two neuronal types. Moreover, an octopamine receptor mRNA is selectively enriched in l-LNvs, and only these neurons respond to in vitro application of octopamine. Dissection and purification of l-LNvs from flies collected at different times indicate that these neurons contain cycling clock mRNAs with higher circadian amplitudes as well as at least a 10-fold higher fraction of oscillating mRNAs than all previous analyses of head RNA. Many of these cycling l-LNv mRNAs are well expressed but do not cycle or cycle much less well elsewhere in heads. The results suggest that RNA cycling is much more prominent in circadian neurons than elsewhere in heads and may be particularly important for the functioning of these neurons.
authors.affiliation: Howard Hughes Medical Institute, National Center for Behavioral Genomics, Department of Biology, Brandeis University, Waltham, MA 02454, USA.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Kula-Eversole
authors.forename: Emi
authors.initials: E
authors.lastname: Nagoshi
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Shang
authors.forename: Joseph
authors.initials: J
authors.lastname: Rodriguez
authors.forename: Ravi
authors.initials: R
authors.lastname: Allada
authors.forename: Michael
authors.initials: M
authors.lastname: Rosbash
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000235:genetics; D002940:Circadian Rhythm / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D017982:Receptors, Biogenic Amine / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020651:Ventral Thalamic Nuclei / Q000166:cytology / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D009479:Neuropeptides; D017982:Receptors, Biogenic Amine; C027604:norsynephrine receptor; C113883:pdf protein, Drosophila; D049452:Green Fluorescent Proteins