Spatial and circadian regulation of cry in Drosophila.
In Drosophila, cryptochrome (cry) encodes a blue-light photoreceptor that mediates light input to circadian oscillators and sustains oscillator function in peripheral tissues. The levels of cry mRNA cycle with a peak at approximately ZT5, which is similar to the phase of Clock (Clk) mRNA cycling in Drosophila. To understand how cry spatial and circadian expression is regulated, a series of cry-Gal4 trans-genes containing different portions of cry upstream and intron 1 sequences were tested for spatial and circadian expression. In fly heads, cry upstream sequences drive constitutive expression in brain oscillator neurons, a novel group of nonoscillator cells in the optic lobe, and peripheral oscillator cells in eyes and antennae. In contrast, cry intron 1 drives rhythmic expression in eyes and antennae, but not brain oscillator neurons. These results demonstrate that intron 1 is sufficient for high-amplitude cry mRNA cycling, show that cry upstream sequences are sufficient for expression in brain oscillator neurons, and suggest that cry spatial and circadian expression are regulated by different elements.
Hao Zheng
Department of Biology and Center for Research on Biological Clocks, Texas A&M University, College Station, TX 77843-3258, USA.
Ng
Fanny
F
Yixiao Liu
Hardin
Paul E
PE
D000818:Animals; D030801:Animals, Genetically Modified; D001683:Biological Clocks / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D056931:Cryptochromes; D004330:Drosophila / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D005136:Eye Proteins / Q000235:genetics / Q000502:physiology*; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation; D007438:Introns; D017956:Photoreceptor Cells, Invertebrate / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000502:physiology*; D019076:Transgenes; D001616:beta-Galactosidase / Q000378:metabolism
D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; C119828:cry protein, Drosophila; D001616:beta-Galactosidase