title: Circadian expression of the presynaptic active zone protein Bruchpilot in the lamina of Drosophila melanogaster.
abstract: In the fly's visual system, the morphology of cells and the number of synapses change during the day. In the present study we show that in the first optic neuropil (lamina) of Drosophila melanogaster, a presynaptic active zone protein Bruchpilot (BRP) exhibits a circadian rhythm in abundance. In day/night (or light/dark, LD) conditions the level of BRP increases two times, in the morning and in the evening. The same pattern of changes in the BRP level was detected in whole brain homogenates, thus indicating that the majority of synapses in the brain peaks twice during the day. However, these two peaks in BRP abundance, measured as the fluorescence intensity of immunolabeling, seem to be regulated differently. The peak in the morning is predominantly regulated by light and involves the transduction pathway in the retina photoreceptors. This peak is present neither in wild-type Canton-S flies in constant darkness (DD), nor in norpA(7) phototransduction mutant in LD. However, it also depends on the clock gene per, because it is abolished in the per(0) arrhythmic mutant. In turn, the peak of BRP in the evening is endogenously regulated by an input from the pacemaker located in the brain. This peak is present in Canton-S flies in DD, as well as in the norpA(7) mutant in LD, but is absent in per(01), tim,(01) and cry(01) mutants in LD. In addition both peaks seem to depend on clock gene-expressing photoreceptors and glial cells of the visual system.
authors.affiliation: Department of Cell Biology and Imaging, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387 Kraków, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Górska-Andrzejak
authors.forename: Renata
authors.initials: R
authors.lastname: Makuch
authors.forename: Joanna
authors.initials: J
authors.lastname: Stefan
authors.forename: Alicja
authors.initials: A
authors.lastname: Görlich
authors.forename: Danuta
authors.initials: D
authors.lastname: Semik
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Pyza
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001485:Basement Membrane / Q000378:metabolism*; D001921:Brain / Q000166:cytology; D002940:Circadian Rhythm / Q000502:physiology*; D056925:Circadian Rhythm Signaling Peptides and Proteins / Q000235:genetics; D003624:Darkness; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster; D005786:Gene Expression Regulation / Q000235:genetics / Q000502:physiology*; D019581:Neuropil / Q000166:cytology* / Q000378:metabolism; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology; D034622:RNA Interference / Q000502:physiology
chemical_list: C510146:BRP protein, Drosophila; D056925:Circadian Rhythm Signaling Peptides and Proteins; D029721:Drosophila Proteins