title: Interactive features of proteins composing eukaryotic circadian clocks.
abstract: Research into the molecular mechanisms of eukaryotic circadian clocks has proceeded at an electrifying pace. In this review, we discuss advances in our understanding of the structures of central molecular players in the timing oscillators of fungi, insects, and mammals. A series of clock protein structures demonstrate that the PAS (Per/Arnt/Sim) domain has been used with great variation to formulate the transcriptional activators and repressors of the clock. We discuss how posttranslational modifications and external cues, such as light, affect the conformation and function of core clock components. Recent breakthroughs have also revealed novel interactions among clock proteins and new partners that couple the clock to metabolic and developmental pathways. Overall, a picture of clock function has emerged wherein conserved motifs and structural platforms have been elaborated into a highly dynamic collection of interacting molecules that undergo orchestrated changes in chemical structure, conformational state, and partners.
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853; email: bc69@cornell.edu.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Crane
authors.forename: Michael W
authors.initials: MW
authors.lastname: Young
mesh_terms: D000818:Animals; D056926:CLOCK Proteins / Q000502:physiology*; D002417:Cattle; D057906:Circadian Clocks / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D004330:Drosophila; D005658:Fungi / Q000502:physiology; D006031:Glycosylation; D006801:Humans; D007313:Insecta / Q000502:physiology; D008027:Light; D010766:Phosphorylation; D010777:Photochemistry / Q000379:methods; D011485:Protein Binding; D011487:Protein Conformation; D025941:Protein Interaction Mapping; D011499:Protein Processing, Post-Translational; D012243:Rhodopsin / Q000502:physiology; D017299:Rod Opsins / Q000502:physiology; D015398:Signal Transduction; D014158:Transcription, Genetic; D000099210:Melanopsin
chemical_list: D056926:CLOCK Proteins; D012243:Rhodopsin; D017299:Rod Opsins; D000099210:Melanopsin
keywords: PAS domain; circadian rhythm; glycosylation; metabolism; phosphorylation; photoentrainment