A Clockwork Organ
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David Whitmore
Abstract
The vertebrate circadian clock was thought to be highly localized to specific anatomical structures: the mammalian suprachiasmatic nucleus (SCN), and the retina and pineal gland in lower vertebrates. However, recent findings in the zebrafish, rat and in cultured cells have suggested that the vertebrate circadian timing system may in fact be highly distributed, with most if not all cells containing a clock.
Our understanding of the clock mechanism has progressed extensively through the use of mutant screening and forward genetic approaches. The first vertebrate clock gene was identified only a few years ago in the mouse by such an approach. More recently, using a syntenic comparative genetic approach, the molecular basis of the the tau mutation in the hamster was determined. The tau gene in the hamster appears to encode casein kinase 1 epsilon, a protein previously shown to be important for PER protein turnover in the Drosophila circadian system. A number of additional clock genes have now been described. These proteins appear to play central roles in the transcription-translation negative feedback loop responsible for clock function. Post-translational modification, protein dimerization and nuclear transport all appear to be essential features of how clocks are thought to tick.
Copyright © 2000 by Walter de Gruyter GmbH & Co. KG
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- Alexander J. Varshavsky Felix Hoppe-Seyler Lecturer 2000
- The Ubiquitin System and the N-End Rule Pathway
- Paper of the Year 1999: Award to Igor Stagljar
- A Clockwork Organ
- The Transgeneticists Toolbox: Novel Methods for the Targeted Modification of Eukaryotic Genomes
- Interdependence of Filamentous Actin and Microtubules for Asymmetric Cell Division
- Genetic Analysis of Mammalian Cyclin-Dependent Kinases and Their Inhibitors
- Phosphorylcholine Substituents in Nematodes: Structures, Occurrence and Biological Implications
- Selenium in Biology: Facts and Medical Perspectives
- The Role of Se, Mo and Fe in the Structure and Function of Carbon Monoxide Dehydrogenase
- Molecular Basis for Interactions of the DnaK Chaperone with Substrates
- Protein Import: the Hitchhikers Guide into Chloroplasts
- Pathway Analysis and Metabolic Engineering in Corynebacterium glutamicum
- Metabolic Networks: a Signal-Oriented Approach to Cellular Models
- Representing and Analysing Molecular and Cellular Function Using the Computer
- Protein Aggregation and Pathogenesis of Huntingtons Disease: Mechanisms and Correlations
- The Mitochondrial Protein Import Motor
- The Immunoglobulin κ Gene Families of Human and Mouse: a Cottage Industry Approach
- Protein-Protein Interactions in Receptor Activation and Intracellular Signalling
- Molecular Genetic Analysis of Glucocorticoid Signaling Using the Cre/loxP System
- Macromolecular Intelligence in Microorganisms
- Thyroid Hormone Receptors Bind to an Element in the Connexin43 Promoter
- Analysis of the Deubiquitinating Enzymes of the Yeast Saccharomyces cerevisiae
- Helical Tubes of FtsZ from Methanococcus jannaschii
- Surface Topography of Microtubule Walls Decorated with Monomeric and Dimeric Kinesin Constructs
- Histone Deacetylase Activity Is Required for the Induction of the MyoD Muscle Cell Lineage in Xenopus
- The Effect of Heat Shock on 20S/26S Proteasomes
- Sec61p Is the Main Ribosome Receptor in the Endoplasmic Reticulum of Saccharomyces cerevisiae
Articles in the same Issue
- Alexander J. Varshavsky Felix Hoppe-Seyler Lecturer 2000
- The Ubiquitin System and the N-End Rule Pathway
- Paper of the Year 1999: Award to Igor Stagljar
- A Clockwork Organ
- The Transgeneticists Toolbox: Novel Methods for the Targeted Modification of Eukaryotic Genomes
- Interdependence of Filamentous Actin and Microtubules for Asymmetric Cell Division
- Genetic Analysis of Mammalian Cyclin-Dependent Kinases and Their Inhibitors
- Phosphorylcholine Substituents in Nematodes: Structures, Occurrence and Biological Implications
- Selenium in Biology: Facts and Medical Perspectives
- The Role of Se, Mo and Fe in the Structure and Function of Carbon Monoxide Dehydrogenase
- Molecular Basis for Interactions of the DnaK Chaperone with Substrates
- Protein Import: the Hitchhikers Guide into Chloroplasts
- Pathway Analysis and Metabolic Engineering in Corynebacterium glutamicum
- Metabolic Networks: a Signal-Oriented Approach to Cellular Models
- Representing and Analysing Molecular and Cellular Function Using the Computer
- Protein Aggregation and Pathogenesis of Huntingtons Disease: Mechanisms and Correlations
- The Mitochondrial Protein Import Motor
- The Immunoglobulin κ Gene Families of Human and Mouse: a Cottage Industry Approach
- Protein-Protein Interactions in Receptor Activation and Intracellular Signalling
- Molecular Genetic Analysis of Glucocorticoid Signaling Using the Cre/loxP System
- Macromolecular Intelligence in Microorganisms
- Thyroid Hormone Receptors Bind to an Element in the Connexin43 Promoter
- Analysis of the Deubiquitinating Enzymes of the Yeast Saccharomyces cerevisiae
- Helical Tubes of FtsZ from Methanococcus jannaschii
- Surface Topography of Microtubule Walls Decorated with Monomeric and Dimeric Kinesin Constructs
- Histone Deacetylase Activity Is Required for the Induction of the MyoD Muscle Cell Lineage in Xenopus
- The Effect of Heat Shock on 20S/26S Proteasomes
- Sec61p Is the Main Ribosome Receptor in the Endoplasmic Reticulum of Saccharomyces cerevisiae
