Light-dependent sequestration of TIMELESS by CRYPTOCHROME.
Most organisms have circadian clocks consisting of negative feedback loops of gene regulation that facilitate adaptation to cycles of light and darkness. In this study, CRYPTOCHROME (CRY), a protein involved in circadian photoperception in Drosophila, is shown to block the function of PERIOD/TIMELESS (PER/TIM) heterodimeric complexes in a light-dependent fashion. TIM degradation does not occur under these conditions; thus, TIM degradation is uncoupled from abrogation of its function by light. CRY and TIM are part of the same complex and directly interact in yeast in a light-dependent fashion. PER/TIM and CRY influence the subcellular distribution of these protein complexes, which reside primarily in the nucleus after the perception of a light signal. Thus, CRY acts as a circadian photoreceptor by directly interacting with core components of the circadian clock.
Ceriani
M F
MF
Department of Cell Biology and NSF Center for Biological Timing, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Darlington
T K
TK
Staknis
D
D
Más
P
P
Petti
A A
AA
Weitz
C J
CJ
Kay
S A
SA
D000818:Animals; D001683:Biological Clocks; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002940:Circadian Rhythm; D056931:Cryptochromes; D003593:Cytoplasm / Q000378:metabolism; D003624:Darkness; D019281:Dimerization; D004330:Drosophila; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins / Q000235:genetics / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D008027:Light; D008164:Luminescent Proteins; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D056950:Period Circadian Proteins; D017956:Photoreceptor Cells, Invertebrate; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins; D019476:Insect Proteins; D008164:Luminescent Proteins; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins; C119828:cry protein, Drosophila; C096445:tim protein, Drosophila; D049452:Green Fluorescent Proteins