title: PERspective on PER phosphorylation.
abstract: Period (PER) proteins are essential parts of the molecular clocks that control circadian rhythms in flies and mammals. Phosphorylation regulates PER's stability and subcellular localization; however, the physiologically relevant sites have been difficult to identify in spite of knowing the relevant kinase. In this issue of Genes & Development, Chiu and colleagues (1758-1772) identify a key phosphorylation site on PER that recruits the F-box protein Slimb to trigger PER degradation and set clock speed.
authors.affiliation: Department of Biology, New York University, New York, New York 10003, USA. justin.blau@nyu.edu
authors.forename: Justin
authors.initials: J
authors.lastname: Blau
mesh_terms: D000818:Animals; D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000378:metabolism; D002940:Circadian Rhythm / Q000502:physiology*; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism*; D056950:Period Circadian Proteins; D010766:Phosphorylation; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; C110233:slmb protein, Drosophila; D044767:Ubiquitin-Protein Ligases