1996/03/22 by Michael P. Myers, Karen Wager‐Smith, Adrian Rothenfluh +1 · 1 citation
Neuroscience · Medicine · Agricultural and Biological Sciences · #Circadian rhythm and melatonin #Spaceflight effects on biology #Light effects on plants #Timeless #Entrainment (biomusicology) #Circadian rhythm #Cryptochrome #Biology #Circadian clock #Bacterial circadian rhythms #Rhythm #Oscillating gene #Cell biology #Light effects on circadian rhythm #Period (music) #CLOCK #Transcription (linguistics) #Drosophila melanogaster #Gene #Neuroscience #Genetics #Internal medicine #Physics #Medicine
paper · doi:10.1126/science.271.5256.1736
openalex publication_date 1996/03/22 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/23
Two genes, period (per) and timeless (tim), are required for production of circadian rhythms in Drosophila. The proteins encoded by these genes (PER and TIM) physically interact, and the timing of their association and nuclear localization is believed to promote cycles of per and tim transcription through an autoregulatory feedback loop. Here it is shown that TIM protein may also couple this molecular pacemaker to the environment, because TIM is rapidly degraded after exposure to light. TIM accumulated rhythmically in nuclei of eyes and in pacemaker cells of the brain. The phase of these rhythms was differentially advanced or delayed by light pulses delivered at different times of day, corresponding with phase shifts induced in the behavioral rhythms.