Roles of the two Drosophila CRYPTOCHROME structural domains in circadian photoreception
Department of Neurobiology
Animals; Animals, Genetically Modified; Cell Line; *Circadian Rhythm; Cysteine Endopeptidases; Darkness; Drosophila Proteins; Drosophila melanogaster; Eye Proteins; Female; *Light; Male; Multienzyme Complexes; Mutation; Nuclear Proteins; Photoreceptors, Invertebrate; Phototransduction; Proteasome Endopeptidase Complex; Protein Binding; Protein Structure, Tertiary; Receptors, G-Protein-Coupled
Life Sciences | Medicine and Health Sciences | Neuroscience and Neurobiology
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.
Rights and Permissions
Citation: Science. 2004 Jun 4;304(5676):1503-6. Link to article on publisher's site