Photic Signaling by Cryptochrome in the Drosophila Circadian System

Oscillations of the period (per) andtimeless (tim) gene products are an integral part of the feedback loop that underlies circadian behavioral rhythms in Drosophila melanogaster. Resetting this loop in response to light requires the putative circadian photoreceptor cryptochrome (CRY). We dissected t...

Full description

Saved in:
Bibliographic Details
Published in:Molecular and cellular biology 2001-11, Vol.21 (21), p.7287-7294
Main Authors: Lin, Fang-Ju, Song, Wei, Meyer-Bernstein, Elizabeth, Naidoo, Nirinjini, Sehgal, Amita
Format: Article
Language:English
Subjects:
Animals
Blotting, Western
Cell Growth and Development
Circadian Rhythm
cryptochrome
Cryptochromes
Cysteine Endopeptidases
Drosophila
Drosophila melanogaster
Drosophila Proteins
Electron Transport
Eye Proteins
Flavoproteins - metabolism
Insect Proteins - physiology
Light
Models, Biological
Multienzyme Complexes - antagonists & inhibitors
Mutation
Nuclear Proteins - physiology
Oxidation-Reduction
period (per) gene
Period Circadian Proteins
Photoreceptor Cells, Invertebrate
Plasmids - metabolism
Precipitin Tests
Proteasome Endopeptidase Complex
Protein Binding
Receptors, G-Protein-Coupled
Reverse Transcriptase Polymerase Chain Reaction
Signal Transduction
TIM protein
Time Factors
timeless (tim) gene
Transfection
Ubiquitin - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Oscillations of the period (per) andtimeless (tim) gene products are an integral part of the feedback loop that underlies circadian behavioral rhythms in Drosophila melanogaster. Resetting this loop in response to light requires the putative circadian photoreceptor cryptochrome (CRY). We dissected the early events in photic resetting by determining the mechanisms underlying the CRY response to light and by investigating the relationship between CRY and the light-induced ubiquitination of the TIM protein. In response to light, CRY is degraded by the proteasome through a mechanism that requires electron transport. Various CRY mutant proteins are not degraded, and this suggests that an intramolecular conversion is required for this light response. Light-induced TIM ubiquitination precedes CRY degradation and is increased when electron transport is blocked. Thus, inhibition of electron transport may "lock" CRY in an active state by preventing signaling required either to degrade CRY or to convert it to an inactive form. High levels of CRY block TIM ubiquitination, suggesting a mechanism by which light-driven changes in CRY could control TIM ubiquitination.
ISSN:0270-7306
1098-5549
1098-5549
DOI:10.1128/MCB.21.21.7287-7294.2001