CRYPTOCHROME (CRY) is the primary circadian photoreceptor in Drosophila. We show that CRY binding to TIMELESS (TIM) is light-dependent in flies and irreversibly commits TIM to proteasomal degradation. In contrast, CRY degradation is dependent on continuous light exposure, indicating that the CRY-TIM interaction is transient. A novel cry mutation (cry(m)) reveals that CRY's photolyase homology domain is sufficient for light detection and phototransduction, whereas the carboxyl-terminal domain regulates CRY stability, CRY-TIM interaction, and circadian photosensitivity. This contrasts with the function of Arabidopsis CRY domains and demonstrates that insect and plant cryptochromes use different mechanisms.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1126/science.1096973 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Dissecting the Interaction between Cryptochrome and Timeless Reveals Underpinnings of Light-Dependent Recognition.
Biochemistry
January 2024
Department of Chemistry & Chemical Biology, Cornell University, Ithaca, New York 14853, United States.
Circadian rhythms are determined by cell-autonomous transcription-translation feedback loops that entrain to environmental stimuli. In the model circadian clock of , the clock is set by the light-induced degradation of the core oscillator protein timeless (TIM) by the principal light-sensor cryptochrome (CRY). The cryo-EM structure of CRY bound to TIM revealed that within the extensive CRY:TIM interface, the TIM N-terminus binds into the CRY FAD pocket, in which FAD and the associated phosphate-binding loop (PBL) undergo substantial rearrangement.
View Article and Find Full Text PDFCryptochrome-Timeless structure reveals circadian clock timing mechanisms.
Nature
May 2023
Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
Circadian rhythms influence many behaviours and diseases. They arise from oscillations in gene expression caused by repressor proteins that directly inhibit transcription of their own genes. The fly circadian clock offers a valuable model for studying these processes, wherein Timeless (Tim) plays a critical role in mediating nuclear entry of the transcriptional repressor Period (Per) and the photoreceptor Cryptochrome (Cry) entrains the clock by triggering Tim degradation in light.
View Article and Find Full Text PDFEntrainment of the Drosophila circadian clock: more heat than light.
Sci STKE
November 2007
Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, MO 64110, USA.
Circadian rhythms are produced by a biological clock that is synchronized (or entrained) by cycles of light and temperature. In Drosophila, light triggers the interaction of the photoreceptor cryptochrome (CRY) with the circadian clock protein timeless (TIM). The absence of this interaction in cryb mutants eliminates this entrainment mechanism.
View Article and Find Full Text PDFRoles of the two Drosophila CRYPTOCHROME structural domains in circadian photoreception.
Science
June 2004
Department of Neurobiology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA.
CRYPTOCHROME (CRY) is the primary circadian photoreceptor in Drosophila. We show that CRY binding to TIMELESS (TIM) is light-dependent in flies and irreversibly commits TIM to proteasomal degradation. In contrast, CRY degradation is dependent on continuous light exposure, indicating that the CRY-TIM interaction is transient.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!