Circadian Clocks: Biological mechanism that controls CIRCADIAN RHYTHM. Circadian clocks exist in the simplest form in cyanobacteria and as more complex systems in fungi, plants, and animals. In humans the system includes photoresponsive RETINAL GANGLION CELLS and the SUPRACHIASMATIC NUCLEUS that acts as the central oscillator.CLOCK Proteins: Basic helix-loop-helix (bHLH) domain-containing proteins that contain intrinsic HISTONE ACETYLTRANSFERASE activity and play important roles in CIRCADIAN RHYTHM regulation. Clock proteins combine with Arntl proteins to form heterodimeric transcription factors that are specific for E-BOX ELEMENTS and stimulate the transcription of several E-box genes that are involved in cyclical regulation. This transcriptional activation also sets into motion a time-dependent feedback loop which in turn down-regulates the expression of clock proteins.Circadian Rhythm: The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs and stimuli, hormone secretion, sleeping, and feeding.Biological Clocks: The physiological mechanisms that govern the rhythmic occurrence of certain biochemical, physiological, and behavioral phenomena.Period Circadian Proteins: Circadian rhythm signaling proteins that influence circadian clock by interacting with other circadian regulatory proteins and transporting them into the CELL NUCLEUS.ARNTL Transcription Factors: Basic helix-loop-helix (bHLH) domain-containing proteins that play important roles in CIRCADIAN RHYTHM regulation. They combine with CLOCK PROTEINS to form heterodimeric transcription factors that are specific for E-BOX ELEMENTS and stimulate the transcription of several E-box genes that are involved in cyclical regulation.Cryptochromes: Flavoproteins that function as circadian rhythm signaling proteins in ANIMALS and as blue-light photoreceptors in PLANTS. They are structurally-related to DNA PHOTOLYASES and it is believed that both classes of proteins may have originated from an earlier protein that played a role in protecting primitive organisms from the cyclical exposure to UV LIGHT.Photoperiod: The time period of daily exposure that an organism receives from daylight or artificial light. It is believed that photoperiodic responses may affect the control of energy balance and thermoregulation.Circadian Rhythm Signaling Peptides and Proteins: A broad category of proteins that regulate the CIRCADIAN RHYTHM of an organism. Included here are proteins that transmit intracellular and intercellular signals in a chronological manner along with proteins that sense light and time-dependent changes in the environment such as the PHOTOPERIOD.Suprachiasmatic Nucleus: An ovoid densely packed collection of small cells of the anterior hypothalamus lying close to the midline in a shallow impression of the OPTIC CHIASM.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Nuclear Receptor Subfamily 1, Group D, Member 1: A DNA-binding orphan nuclear receptor that negatively regulates expression of ARNTL TRANSCRIPTION FACTORS and plays a role as a regulatory component of the circadian clock system. The Nr1d1 nuclear receptor expression is cyclically-regulated by a feedback loop involving its positive regulation by CLOCK PROTEIN; BMAL1 PROTEIN heterodimers and its negative regulation by CRYPTOCHROME and PERIOD PROTEINS.FlavoproteinsDarkness: The absence of light.Feedback, Physiological: A mechanism of communication with a physiological system for homeostasis, adaptation, etc. Physiological feedback is mediated through extensive feedback mechanisms that use physiological cues as feedback loop signals to control other systems.Chronobiology Disorders: Disruptions of the rhythmic cycle of bodily functions or activities.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Casein Kinase Iepsilon: A casein kinase I isoenzyme with specificity for proteins involved the regulation of the CIRCADIAN RHYTHM.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Photoreceptor Cells, Invertebrate: Specialized cells in the invertebrates that detect and transduce light. They are predominantly rhabdomeric with an array of photosensitive microvilli. Illumination depolarizes invertebrate photoreceptors by stimulating Na+ influx across the plasma membrane.Basic Helix-Loop-Helix Transcription Factors: A family of DNA-binding transcription factors that contain a basic HELIX-LOOP-HELIX MOTIF.Gene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.Synechococcus: A form-genus of spherical to rod-shaped CYANOBACTERIA in the order Chroococcales. They contain THYLAKOIDS and are found in a wide range of habitats.Drosophila Proteins: Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.Neurospora crassa: A species of ascomycetous fungi of the family Sordariaceae, order SORDARIALES, much used in biochemical, genetic, and physiologic studies.Activity Cycles: Bouts of physical irritability or movement alternating with periods of quiescence. It includes biochemical activity and hormonal activity which may be cellular. These cycles are shorter than 24 hours and include sleep-wakefulness cycles and the periodic activation of the digestive system.Nuclear Proteins: Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.Light Signal Transduction: The conversion of absorbed light energy into molecular signals.Melatonin: A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.E-Box Elements: DNA locations with the consensus sequence CANNTG. ENHANCER ELEMENTS may contain multiple copies of this element. E-boxes play a regulatory role in the control of transcription. They bind with basic helix-loop-helix (bHLH) type TRANSCRIPTION FACTORS. Binding specificity is determined by the specific bHLH heterodimer or homodimer combination and by the specific nucleotides at the 3rd and 4th position of the E-box sequence.Pineal Gland: A light-sensitive neuroendocrine organ attached to the roof of the THIRD VENTRICLE of the brain. The pineal gland secretes MELATONIN, other BIOGENIC AMINES and NEUROPEPTIDES.Casein Kinase Idelta: A casein kinase I isoenzyme that plays a regulatory role in a variety of cellular functions including vesicular transport, CHROMOSOME SEGREGATION; CYTOKINESIS, developmental processes, and the CIRCADIAN RHYTHM.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Jet Lag Syndrome: A chronobiologic disorder resulting from rapid travel across a number of time zones, characterized by insomnia or hypersomnolence, fatigue, behavioral symptoms, headaches, and gastrointestinal disturbances. (From Cooper, Sleep, 1994, pp593-8)Drug Chronotherapy: The adaptation of drug administration to the known variations in biological RHYTHMICITY, such as CIRCADIAN RHYTHMS. The treatment is aimed at supporting normal rhythms, or modifying the timing of therapy to achieve maximal efficacy and minimal adverse effect.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Oscillometry: The measurement of frequency or oscillation changes.Cell Cycle Proteins: Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.Mammals: Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.Periodicity: The tendency of a phenomenon to recur at regular intervals; in biological systems, the recurrence of certain activities (including hormonal, cellular, neural) may be annual, seasonal, monthly, daily, or more frequently (ultradian).Neurospora: A genus of ascomycetous fungi, family Sordariaceae, order SORDARIALES, comprising bread molds. They are capable of converting tryptophan to nicotinic acid and are used extensively in genetic and enzyme research. (Dorland, 27th ed)Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Flowers: The reproductive organs of plants.Drosophila: A genus of small, two-winged flies containing approximately 900 described species. These organisms are the most extensively studied of all genera from the standpoint of genetics and cytology.Arylalkylamine N-Acetyltransferase: An acetyltransferase with specificity towards the amine group of aromatic alkylamines (arylalkylamines) such as SEROTONIN. This enzyme is also referred to as serotonin acetylase despite the fact that serotonin acetylation can also occur through the action of broad specificity acetyltransferases such as ARYLAMINE N-ACETYLTRANSFERASE.Hypocotyl: The region of the stem beneath the stalks of the seed leaves (cotyledons) and directly above the young root of the embryo plant. It grows rapidly in seedlings showing epigeal germination and lifts the cotyledons above the soil surface. In this region (the transition zone) the arrangement of vascular bundles in the root changes to that of the stem. (From Concise Dictionary of Biology, 1990)Drosophila melanogaster: A species of fruit fly much used in genetics because of the large size of its chromosomes.Genes, Plant: The functional hereditary units of PLANTS.Diapause, Insect: Seasonal suspension of insect growth development. It can be either induced by environmental cues (e.g., PHOTOPERIOD) or as a facultative part of the life cycle in order to time development with seasonal changes.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Eye ProteinsPhytochrome: A blue-green biliprotein widely distributed in the plant kingdom.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Luciferases: Enzymes that oxidize certain LUMINESCENT AGENTS to emit light (PHYSICAL LUMINESCENCE). The luciferases from different organisms have evolved differently so have different structures and substrates.Cyanobacteria: A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Photobiology: The branch of biology dealing with the effect of light on organisms.Animals, Genetically Modified: ANIMALS whose GENOME has been altered by GENETIC ENGINEERING, or their offspring.Phytochrome B: A plant photo regulatory protein that exists in two forms that are reversibly interconvertible by LIGHT. In response to light it moves to the CELL NUCLEUS and regulates transcription of target genes. Phytochrome B plays an important role in shade avoidance and mediates plant de-etiolation in red light.Time Factors: Elements of limited time intervals, contributing to particular results or situations.NIH 3T3 Cells: A continuous cell line of high contact-inhibition established from NIH Swiss mouse embryo cultures. The cells are useful for DNA transfection and transformation studies. (From ATCC [Internet]. Virginia: American Type Culture Collection; c2002 [cited 2002 Sept 26]. Available from http://www.atcc.org/)Mice, Inbred C57BLNuclear Receptor Subfamily 1, Group F, Member 1: A DNA-binding orphan nuclear receptor that positively regulates expression of ARNTL TRANSCRIPTION FACTORS and is a regulatory component of the circadian clock system. The protein also has a role in neuron cell survival and differentiation in that loss of function mutations of its gene result in the mouse phenotype referred to as the STAGGERER MOUSE.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Luminescence: Emission of LIGHT when ELECTRONS return to the electronic ground state from an excited state and lose the energy as PHOTONS. It is sometimes called cool light in contrast to INCANDESCENCE. LUMINESCENT MEASUREMENTS take advantage of this type of light emitted from LUMINESCENT AGENTS.Chronobiology Phenomena: Biological systems as affected by time. Aging, biological rhythms, and cyclic phenomena are included. Statistical, computer-aided mathematical procedures are used to describe, in mathematical terminology, various biological functions over time.Casein Kinase I: A casein kinase that was originally described as a monomeric enzyme with a molecular weight of 30-40 kDa. Several ISOENZYMES of casein kinase I have been found which are encoded by separate genes. Many of the casein kinase I isoenzymes have been shown to play distinctive roles in intracellular SIGNAL TRANSDUCTION.Behavior, Animal: The observable response an animal makes to any situation.Rod Opsins: Photosensitive proteins expressed in the ROD PHOTORECEPTOR CELLS. They are the protein components of rod photoreceptor pigments such as RHODOPSIN.Sleep Disorders, Circadian Rhythm: Dyssomnias associated with disruption of the normal 24 hour sleep wake cycle secondary to travel (e.g., JET LAG SYNDROME), shift work, or other causes.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Chronotherapy: The adaptation of therapeutic approaches such as pharmacological (DRUG CHRONOTHERAPY), surgical, radiological, or physical to the known variations in biological RHYTHMICITY, such as CIRCADIAN RHYTHMS. The treatment is aimed at supporting normal rhythms, or modifying the timing of therapy to achieve maximal efficacy and minimal adverse effect.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Feedback: A mechanism of communication within a system in that the input signal generates an output response which returns to influence the continued activity or productivity of that system.Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.Neuropeptides: Peptides released by NEURONS as intercellular messengers. Many neuropeptides are also hormones released by non-neuronal cells.Sleep: A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Solar System: The group of celestial bodies, including the EARTH, orbiting around and gravitationally bound by the sun. It includes eight planets, one minor planet, and 34 natural satellites, more than 1,000 observed comets, and thousands of lesser bodies known as MINOR PLANETS (asteroids) and METEOROIDS. (From Academic American Encyclopedia, 1983)Mesocricetus: A genus of the family Muridae having three species. The present domesticated strains were developed from individuals brought from Syria. They are widely used in biomedical research.Insect Proteins: Proteins found in any species of insect.Receptors, G-Protein-Coupled: The largest family of cell surface receptors involved in SIGNAL TRANSDUCTION. They share a common structure and signal through HETEROTRIMERIC G-PROTEINS.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Locomotion: Movement or the ability to move from one place or another. It can refer to humans, vertebrate or invertebrate animals, and microorganisms.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Luminescent Measurements: Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.Genes, Insect: The functional hereditary units of INSECTS.Moon: The natural satellite of the planet Earth. It includes the lunar cycles or phases, the lunar month, lunar landscapes, geography, and soil.Plant Physiological Phenomena: The physiological processes, properties, and states characteristic of plants.Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Fungal Proteins: Proteins found in any species of fungus.Fagaceae: A plant family of the order Fagales subclass Hamamelidae, class Magnoliopsida.Zebrafish: An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.Heteroptera: A suborder of HEMIPTERA, called true bugs, characterized by the possession of two pairs of wings. It includes the medically important families CIMICIDAE and REDUVIIDAE. (From Dorland, 28th ed)Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Lighting: The illumination of an environment and the arrangement of lights to achieve an effect or optimal visibility. Its application is in domestic or in public settings and in medical and non-medical environments.Phytochrome A: The primary plant photoreceptor responsible for perceiving and mediating responses to far-red light. It is a PROTEIN-SERINE-THREONINE KINASE that is translocated to the CELL NUCLEUS in response to light signals.Homeostasis: The processes whereby the internal environment of an organism tends to remain balanced and stable.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Retina: The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Receptors, Vasoactive Intestinal Peptide, Type II: A pituitary adenylate cyclase-activating peptide receptor subtype found in LYMPHOCYTES. It binds both PACAP and VASOACTIVE INTESTINAL PEPTIDE and regulates immune responses.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Wakefulness: A state in which there is an enhanced potential for sensitivity and an efficient responsiveness to external stimuli.Receptors, Melatonin: A family of G-protein-coupled receptors that are specific for and mediate the effects of MELATONIN. Activation of melatonin receptors has been associated with decreased intracellular CYCLIC AMP and increased hydrolysis of PHOSPHOINOSITIDES.Photoreceptor Cells: Specialized cells that detect and transduce light. They are classified into two types based on their light reception structure, the ciliary photoreceptors and the rhabdomeric photoreceptors with MICROVILLI. Ciliary photoreceptor cells use OPSINS that activate a PHOSPHODIESTERASE phosphodiesterase cascade. Rhabdomeric photoreceptor cells use opsins that activate a PHOSPHOLIPASE C cascade.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.F-Box Proteins: A family of proteins that share the F-BOX MOTIF and are involved in protein-protein interactions. They play an important role in process of protein ubiquition by associating with a variety of substrates and then associating into SCF UBIQUITIN LIGASE complexes. They are held in the ubiquitin-ligase complex via binding to SKP DOMAIN PROTEINS.Cyanothece: A form-genus of unicellular coccoid to rod-shaped CYANOBACTERIA, in the order Chroococcales. Three different clusters of strains from diverse habitats are included.
The circadian clock has its own set of genes.[39] Genes which may influence sleep include ABCC9,[40] DEC2,[41][42] and variants ... An organism whose circadian clock exhibits a regular rhythm corresponding to outside signals is said to be entrained; an ... The internal circadian clock is profoundly influenced by changes in light, since these are its main clues about what time it is ... Short pulses of light, at the right moment in the circadian cycle, can significantly 'reset' the internal clock.[24] Blue light ...
Brown, S. A. & Azzi, A. (2013). "Peripheral circadian oscillators in mammals". Circadian clocks. Berlin: Springer. pp. 45-66. ... When travelling across a number of time zones, the body clock (circadian rhythm) will be out of synchronisation with the ... There are two separate processes related to biological timing: circadian oscillators and homeostasis. The circadian system is ... The symptoms are caused by a circadian rhythm that is out of sync with the day-night cycle of the destination, as well as the ...
... role to mediate CLOCK phosphorylation and repress CLOCK-dependent transcription within the Drosophila circadian clock". ... This oscillator, or "circadian clock," is made up of a transcription-translation negative feedback loop (TTNFL) in which ... Harms E, Young MW, Saez L (2003). "CK1 and GSK3 in the Drosophila and mammalian circadian clock". Novartis Foundation Symposium ... Ko CH, Takahashi JS (Oct 2006). "Molecular components of the mammalian circadian clock". Human Molecular Genetics. 15 Spec No 2 ...
Thus, circadian control of clock controlled genes that function in cell growth control and DNA damage response may affect the ... A homolog of CLOCK plays the same role in the human clock, and CYC is replaced by BMAL1. CRY has two human homologs, CRY1 and ... The mammalian period 1 and period 2 genes play key roles in photoentrainment of the circadian clock to light pulses. This was ... Griffin EA, Staknis D, Weitz CJ (October 1999). "Light-independent role of CRY1 and CRY2 in the mammalian circadian clock". ...
The molecular circadian clock of D. melanogaster can be described as a feedback loop of transcription and translation, in which ... These results demonstrated a role for BDBT in the circadian clock. When BDBT was overexpressed, Price found that the ... 2017.[1] Dunlap, JC (1999). "Molecular bases for circadian clocks". Cell. 96 (2): 271-290. doi:10.1016/S0092-8674(00)80566-8. ... reliable phase markers for the Drosophila circadian clock. Price and Seghal mapped the mutations to chromosome 2 and termed the ...
... but both WC-1 and WC-2 are required for the circadian clock to run. Because the core of the clock is based on a rhythmic ... The White Collar Complex (WCC), the heterodimer of WC-1 and WC-2, acts as a positive element in the circadian clock. WCC serves ... Crosthwaite SK, Loros JJ, Dunlap JC (Jun 1995). "Light-induced resetting of a circadian clock is mediated by a rapid increase ... Cha J, Zhou M, Liu Y (2015). "Methods to study molecular mechanisms of the Neurospora circadian clock". Methods in Enzymology. ...
Despite these genes being identified as necessary genes to the circadian clock, there was a variety of levels of expressions in ... July 1999). "mCRY1 and mCRY2 Are Essential Components of the Negative Limb of the Circadian Clock Feedback Loop". Cell. 98: 193 ... Dunlap, JC (January 1999). "Molecular Bases for Circadian Clocks". Cell. 96: 271-290. doi:10.1016/S0092-8674(00)80566-8. PMID ... "Role of the CLOCK Protein in the Mammalian Circadian Mechanism". Science. 280 (5369): 1564-1569. doi:10.1126/science.280.5369. ...
WC-1 and WC-2 are analogous to Bmal and Clock proteins in the Mouse and Drosophila circadian systems in their positive ... Since then, Neurospora has become a model organism for studying circadian clocks and rhythms. WC-1 was first discovered from a ... Collett, Michael A.; Dunlap, Jay C.; Loros, Jennifer J. (2017-04-14). "Circadian Clock-Specific Roles for the Light Response ... Both the Clock Box and PLRE are involved in achieving maximal light induction, and the Clock Box is essential for maintaining ...
CRY1 and CRY2 act as light-independent inhibitors of CLOCK-BMAL1 components of the circadian clock. In plants, blue-light ... Therefore, CRY is involved in light perception and is an input to the circadian clock, however it is not the only input for ... This light regulation of CRY protein levels suggests that CRY has a circadian role upstream of other clock genes and components ... Sancar A, Lindsey-Boltz LA, Kang TH, Reardon JT, Lee JH, Ozturk N (June 2010). "Circadian clock control of the cellular ...
Metz HS (2003). "Light and the circadian clock". J AAPOS. 7 (4): 229-30. doi:10.1016/S1091-8531(03)00119-8. PMID 12917606. Metz ...
The change in the phenotype can be a result of genetic modification of circadian clock gene, HFD, disruption of the circadian ... Eckel-Mahan, Kristin; Sassone-Corsi, Paolo (2016-11-13). "Metabolism and the Circadian Clock Converge". Physiological Reviews. ... The changes in the light/dark cycle of laboratories can alter their circadian rhythm which can affect their metabolism. Besides ... that several studies used genetically modified mouse models that have decreased circadian rhythmicity gene. These cases have ...
She has also worked to describe circadian clocks in mutant or model genetic organisms lacking clear circadian phenotypes. ... Merrow is well known for her work on the entrainment of circadian clocks in both humans and the fungus Neurospora crassa. ... Her career focuses primarily on investigating the molecular and genetic mechanisms of the circadian clock. Since joining the ... The group attempts to improve health through an understanding of circadian clocks and their entrainment. This consortium has ...
Johnson, C.H.; Hastings, J.W. (1986). "The elusive mechanism of the circadian clock". American Scientist. 74: 29-36. Hastings, ... clock". J. Exp. Biol. 97: 121-136. Dunlap, J.; Hastings, J.W. (1981). "The biological clock in Gonyaulax. controls luciferase ... early evidence of the molecular mechanisms of circadian clock regulation in organisms (first using dinoflagellate luminescence ... and was one of the founders of the field of circadian biology (the study of circadian rhythms, or the sleep-wake cycle). He was ...
CLOCK is a circadian rhythm master regulator that functions with BMAL1 to carry out its HAT activity. Three important nuclear ... Doi M, Hirayama J, Sassone-Corsi P (May 2006). "Circadian regulator CLOCK is a histone acetyltransferase". Cell. 125 (3): 497- ... The HAT activities of the human TAFII250 and CLOCK coactivators have not been studied as extensively. TAFII250 is one of the ... These include p300/CBP, nuclear receptor coactivators (e.g., ACTR/SRC-1), TAFII250, TFIIIC, Rtt109, and CLOCK. p300/CBP are ...
"Dr Akhilesh Reddy Bio at the Lister Institute". O'Neill, John S.; Reddy, Akhilesh B. (26 January 2011). "Circadian clocks in ... Reddy's research group discovered the existence of circadian clocks in human red blood cells (erythrocytes) in 2011. With ... Therefore, his group discovered circadian rhythms without the formation of new RNA in higher organisms for the first time. In ... "Circadian rhythms persist without transcription in a eukaryote". Nature. 469 (7331): 554-558. doi:10.1038/nature09654. PMC ...
The core mammalian circadian clock is a negative feedback loop which consists of Per1/Per2, Cry1/Cry2, Bmal1, and Clock. This ... Ko CH, Takahashi JS (October 2006). "Molecular components of the mammalian circadian clock". Human Molecular Genetics. 15 Spec ... Zhao X, Cho H, Yu RT, Atkins AR, Downes M, Evans RM (May 2014). "Nuclear receptors rock around the clock". EMBO Reports. 15 (5 ... PDP1 and VRI in Drosophila regulate circadian rhythm's by competing for the same binding site, the VP box, similarly to how ROR ...
The latter may be based on external time-cues (Zeitgebers), or internally generated circadian rhythms ("biological clock"). TPL ... "Circadian clocks and memory: Time-place learning". Frontiers in Molecular Neuroscience. 6: 1-10. doi:10.3389/fnmol.2013.00008. ... hourglass or circadian clock?". Journal of Biological Rhythms. 6: 353-365. doi:10.1177/074873049100600406. Wenger, D.; Biebach ... As with circadian rhythms of activity, the spatio-temporal pattern of room visits shifted gradually over several days following ...
Central and peripheral circadian clocks in mammals. Annu Rev Neurosci. 2012; 35:445-62. doi:10.1146/annurev-neuro-060909-153128 ... Other examples include Central and peripheral circadian clocks, and central versus peripheral vision. These two terms relate to ...
Subjects are thus forced to live by their internal circadian "clocks". The individual's or animal's circadian phase can be ... specifically without an alarm clock or reference to the time of day). Circadian rhythm Circadian rhythm sleep disorder Scheer, ... Image forming vision (rods and cones) is not required ... for synchronising/phase shifting the circadian clock. A collection of ... These ganglion cells, which contain melanopsin, convey their signals to the "circadian clock" via the retinohypothalamic tract ...
"The circadian clock: from molecules to behaviour". Ann. Med. 27 (4): 481-90. doi:10.3109/07853899509002457. PMID 8519510. ... There is good evidence that some basic aspects of human behaviour, such as circadian rhythms are genetically-based, but it is ...
O'Neill JS, Reddy AB (January 2011). "Circadian clocks in human red blood cells". Nature. 469 (7331): 498-503. doi:10.1038/ ... Peroxiredoxins have been implicated in the 24-hour internal circadian clock of many organisms. Catalase Oxidative stress ... O'Neill JS, van Ooijen G, Dixon LE, Troein C, Corellou F, Bouget FY, Reddy AB, Millar AJ (January 2011). "Circadian rhythms ... Bass J, Takahashi JS (January 2011). "Circadian rhythms: Redox redux". Nature. 469 (7331): 476-8. doi:10.1038/469476a. PMC ...
... the primary circadian pacemaker in the mammalian brain. Genes in this family encode components of the circadian clock, which ... Griffin EA, Staknis D, Weitz CJ (Oct 1999). "Light-independent role of CRY1 and CRY2 in the mammalian circadian clock". Science ... This negative feedback loop is essential for maintaining a functioning circadian clock. A disruption of either both mPER1 and ... So AY, Bernal TU, Pillsbury ML, Yamamoto KR, Feldman BJ (Oct 2009). "Glucocorticoid regulation of the circadian clock modulates ...
Modeling of a human circadian mutation yields insights into clock regulation by PER2. Cell. 2007 Jan 12:128(1):59-70. Kaasik K ... Fu's lab identified two rare variants in the circadian clock gene PERIOD3 (PER3-P415A/H417R) in individuals with familial ... Glucose sensor O-GlcNAcylation coordinates with phosphorylation to regulate circadian clock. Cell Metab. 2013 Feb 5; 17(2):291- ... Ko, Caroline H.; Takahashi, Joseph S. (2006-10-15). "Molecular components of the mammalian circadian clock". Human Molecular ...
Later work revealed that BMAL1 is the only clock gene without which the circadian clock fails to function in humans. BMAL1 ... The result has been the creation of pages about genes involved in the circadian clock such as ARNTL, as well as pages about ... Scientists Unwind a Circadian Clock Mystery, Genetic Engineering and Biotechnology News, April 16, 2014, retrieved April 23, ... October 2, 2009). "A Genome-wide RNAi Screen for Modifiers of the Circadian Clock in Human Cells". Cell. 139 (1): 199-210. doi: ...
Allada R, White NE, So WV, Hall JC, Rosbash M (May 1998). "A mutant Drosophila homolog of mammalian Clock disrupts circadian ... Tanoue S, Krishnan P, Krishnan B, Dryer SE, Hardin PE (April 2004). "Circadian clocks in antennal neurons are necessary and ... Research from 2012 on sleep architecture and nutrition found that circadian clock mutants, including cyc01 still maintained a ... Helfrich-Förster C (March 2005). "Neurobiology of the fruit fly's circadian clock". Genes, Brain, and Behavior. 4 (2): 65-76. ...
"Circadian Rhythm Sleep Disorder" (PDF). American Academy of Sleep Medicine. 2008. Archived from the original (PDF) on 2010-08- ... Blind people may use talking equipment such as thermometers, watches, clocks, scales, calculators, and compasses. They may also ... a condition in which a person's circadian rhythm, normally slightly longer than 24 hours, is not entrained (synchronized) to ... "Circadian rhythm abnormalities in totally blind people: incidence and clinical significance". J. Clin. Endocrinol. Metab. 75 ...
CRD is a sleep disorder characterized by a discrepancy between the internal setting of ones circadian clock, and the sleep ... Circadian rhythms run on a 23.5 to 24.5 hour cycle. Our circadian rhythms are regulated by external cues, such as availability ... Comorbidity of Circadian Rhythm Sleep Disorder. Insufficient sleep and working against ones circadian rhythm is associated with ... Onset of Circadian Rhythm Sleep Disorder. The DSM-5 does not specify an age of onset for CRSD. As noted in the diagnostic ...
Circadian clocks and mood-related behaviors. Handb Exp Pharmacol 2013:227-39. 14. Hampp G, Albrecht U. The circadian clock and ... The clock genes are involved in the generation of the circadian rhythms and the biological clock is synchronized to solar day ... Suprachiasmatic nucleus: the brains circadian clock. Recent prog Horm Res 1999;54:33-58.. 4. Moore RY. Circadian rhythms: ... Biological clock and circadian rhythms are useful if they can be adjusted to the local time, allowing ones alertness level to ...
In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. ...
Variation in circadian clocks[edit]. While a precise 24-hour circadian clock is found in many organisms, it is not universal. ... Plant clocks[edit]. The circadian clock in plants has completely different components to those in the animal, fungus or ... A circadian clock, or circadian oscillator, is a biochemical oscillator that cycles with a stable phase and is synchronized ... Mammalian clocks[edit]. Selective gene knockdown of known components of the human circadian clock demonstrates both active ...
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Circadian Rhythms and Circadian Clock. Circadian Rhythms. *Are internally driven cycles that rise and fall during the 24-hour ... Circadian Clock. The circadian clock has an internally driven 24-hour rhythm that tends to run longer than 24 hours but resets ... The master circadian clock in the brain (see Figure 2) synchronizes and controls these cycles so they work together. ... The internal body clock sets the timing for many circadian rhythms, which regulate processes such as ...
Most clocks use the light-dark cycle as environmental signal (zeitgeber) for this active synchronisation. How we... ... The circadian clock can only reliably fulfil its function if it is stably entrained. ... Light and the Human Circadian Clock. In: Kramer A., Merrow M. (eds) Circadian Clocks. Handbook of Experimental Pharmacology, ... The circadian clock can only reliably fulfil its function if it is stably entrained. Most clocks use the light-dark cycle as ...
... but blogging audience forces me to occasionally look into human clocks from a medical perspective. ... You probably realize by now that my expertise is in clocks and calendars of birds, ... Molecular Mechanism of Circadian Rhythm Generation in Mammals. Let me now try to explain how the mammalian circadian clock ... Clocks and Bipolar Disorder. This is an interesting short review about the link between the circadian clock and the manic/ ...
Circadian clock cryptochrome proteins regulate autoimmunity. Qi Cao, Xuan Zhao, Jingwen Bai, Sigal Gery, Haibo Sun, De-Chen Lin ... C1qa, C1qb, C1qc, C6, Fcgr3, and Fcgr4 were down-regulated, and circadian clock genes Per2, Per3, Nr1d1, and Nr1d2 were up- ... 2012) Circadian expression of clock genes in mouse macrophages, dendritic cells, and B cells. Brain Behav Immun 26:407-413. ... indicating that the intrinsic circadian clock regulates inflammatory innate immune functions (11). The circadian oscillations ...
If you ever glanced at the circadian literature, you have probably encountered the statement that circadian rhythms are ... Clocks in Bacteria III: Evolution of Clocks in Cyanobacteria, Clocks in Bacteria IV: Clocks in other bacteria, Clocks in ... Circadian Clocks in Microorganisms, Clocks in Bacteria I: Synechococcus elongatus, Clocks in Bacteria II: Adaptive Function of ... Clocks in Bacteria IV: Clocks in other bacteria. Fourth in the five-part series on clocks in bacteria (from April 30, 2006): ...
... in the brain has a master circadian clock that manages cells, many of which have their own molecular clocks. ... According to the Cleveland Clinic, the circadian rhythm, otherwise known as the "internal body clock," manages the body´s 24- ... This study is the first to definitively prove that the body´s circadian biological clock controls insulin activity. ... The researchers used different approaches to disrupt the circadian clocks of individual mice. Measurements were taken at ...
However, FRP or clock-null mutations of circadian clock genes in Drosophila (per) or Neurospora (frq) do not obviously impair ... The Circadian Clock in Arabidopsis Roots Is a Simplified Slave Version of the Clock in Shoots ... The circadian clock controls the expression pattern of the circadian input photoreceptor, phytochrome B ... Quinone sensing by the circadian input kinase of the cyanobacterial circadian clock ...
Compelling evidence points toward a tight intertwining between circadian rhythms and metabolism. Circadian clocks play a major ... The mammalian circadian timing system consists of a central pacemaker in the brain that synchronizes subsidiary oscillators in ... Concomitantly, clocks are tightly coupled to cellular metabolism and respond to feeding cycles. Our overarching goal is to ... While the brains master clock is entrained by daily light-dark cycles, feeding time appears to be the dominant timing cue for ...
... 25.09.2015. A circadian clock is not mandatory for living beings to adapt their activities to a ... The circadian clock sets the pace. Nevertheless, clockless fruit flies do show some behavioural differences. The clock seems to ... But this view of circadian clocks as central mechanisms that drive circadian rhythms was recently challenged. Scientists had ... And ideally its circadian clock will make the animal stop its activities before it is dark the next day. ...
Circadian clock molecules in flies. The expression of circadian timing in individual neurones shows that it is not an emergent ... Circadian clock molecules in mammals. Studies in mammals have advanced our understanding of the clock mechanism in two ways. ... Circadian clock molecules in drosophila. Early cycle: Expression of the clock genes period (per) and timeless (tim) is ... hence circadian (approximately a day). Notwithstanding this inaccuracy, the circadian clock is extremely robust. It is capable ...
The kidneys contain a circadian clock that plays a key role in levels of certain blood components - such as lipids and amino ... Kidneys circadian clock regulates drug disposition, blood component levels. Published Friday 8 April 2016 Published Fri 8 Apr ... "Kidneys circadian clock regulates drug disposition, blood component levels." Medical News Today. MediLexicon, Intl., 8 Apr. ... The circadian clock is the bodys natural time-keeping mechanism, located in the suprachiasmatic nucleus of the brain. It ...
... to pathogenic invasion is controlled by circadian rhythms, researchers found. ... Circadian Clock Times Immune Response. The molecular response of an organism -- be it mouse or man -- to pathogenic invasion is ... To examine the influence of the circadian clock on immunity at the molecular level, Fikrigs group conducted a series of murine ... Source Reference: Silver A, et al "The circadian clock controls tool-like receptor 9-mediated innate and adaptive immunity" ...
"CIRCADIAN CLOCK ASSOCIATED1 and LATE ELONGATED HYPOCOTYL Function Synergistically in the Circadian Clock of Arabidopsis" Plant ... Circadian Clock Associated 1 (CCA1) is a gene that is central to the circadian oscillator of angiosperms. It was first ... The evolution of circadian clocks in land plants is not understood, because circadian rhythms have received little attention in ... "Loss of the circadian clock-associated protein 1 in Arabidopsis results in altered clock-regulated gene expression." Proc Natl ...
The molecular mechanisms of the clock are being studied at the biochemical and genomic levels. ... Joseph Takahashi is interested in understanding the genetic and molecular basis of circadian rhythms as well as other complex ... The Clock mutation lengthens circadian period by 4 hours in homozygous mutants, followed by a complete loss of circadian ... Molecular Mechanism of the Clock. The circadian clock in mammals is composed of an autoregulatory transcriptional network with ...
A new study now shows that a central clock governs the circadian rhythms in certain cases. ... Whether and how these clocks are connected with each other is still a largely open question. ... Multiple biological clocks control the daily rhythms of physiology and behavior in animals and humans. ... Rather, most organisms have a multitude of circadian clocks: a central clock in the brain and various peripheral clocks in the ...
Circadian clocks provide a competitive advantage in an environment that is heavily influenced by the rotation of the Earth, by ... Photosynthetic entrainment of the Arabidopsis thaliana circadian clock.. Haydon MJ1, Mielczarek O, Robertson FC, Hubbard KE, ... The production of sugars by photosynthesis is a key metabolic output of the circadian clock in plants. Here we show that these ... Circadian clocks comprise transcription-translation feedback loops, which are entrained by environmental signals such as light ...
This book sheds new light on the molecular mechanisms that generate circadian rhythms. It examines how biological rhythms ... Mammalian Circadian Clocks and Metabolism: Navigating Nutritional Challenges in a Rhythmic World ... This book sheds new light on the molecular mechanisms that generate circadian rhythms. It examines how biological rhythms ... this book serves as a guide for physicians and scientists who wish to learn more about the impact of circadian rhythms on ...
Further clues into the regulation of circadian clocks are the subject of two reports. In plants and insects, cryptochromes ( ... In Drosophila, three of the critical clock genes, period (per), timeless (tim), and Drosophila Clock (dClk), are expressed ... role of CRY1 and light-independent role of CRY1 and light-iIndependent role of CRY1 and CRY2 in the mammalian circadian clock. ... show that CRY1 and CRY2 play a central role in the mammal clock, but in a light-independent fashion--they appear to regulate ...
Per3 period circadian clock 3 [Mus musculus] Per3 period circadian clock 3 [Mus musculus]. Gene ID:18628 ... period circadian protein homolog 3. Names. circadian clock protein PERIOD 3. period homolog 3. ... Circadian rhythm, organism-specific biosystemCircadian rhythm is an internal biological clock, which enables to sustain an ... Circadian rhythm, conserved biosystemCircadian rhythm is an internal biological clock, which enables to sustain an ...
Dartmouth researchers have found evidence of two circadian clocks working within the same tissue of the plant Arabidopsis ... McClung and his students continued the study by examining how the circadian clocks were reset by different stimuli. For example ... Dartmouth researchers have found evidence of two circadian clocks working within the same tissue of the plant Arabidopsis ... Having two clocks with different sensitivities to light and to temperature is a better way to ensure that both signals of ...
  • CRSD (Circadian Rhythm Sleep Disorder) is a DSM-5 (Diagnostic and Statistical Manual of mental Disorders, fifth edition) class of sleep disorders in which one's internal sleep wake clock is disrupted, resulting in disturbed sleep and consequential daytime fatigue (American Psychiatric Association, 2013). (theravive.com)
  • PTTH neurons (green) connect the circadian clock (magenta) of the brain with the peripheral clock in the prothoracic gland. (eurekalert.org)
  • In their search for the connecting pathway, the Würzburg scientists concentrated on specific neurons that could facilitate the contact between the central and the peripheral clock, the so-called PTTH neurons. (eurekalert.org)
  • In fact, the Würzburg scientists were able to show that the PTTH neurons establish a direct link between the brain-based clock of the fruit fly and its peripheral counterpart. (eurekalert.org)
  • They showed in experiments that the central clock neurons produce a special neuropeptide which transmits time information to the PTTH neurons. (eurekalert.org)
  • Now, for the first time, a team of neuroscientists at Beth Israel Deaconess Medical Center (BIDMC) has demonstrated circadian control of aggression in male mice and identified the specific neurons and circuitry regulating the daily pattern. (medindia.net)
  • Next, the scientists used genetics-based tools to manipulate neurons known to regulate the central circadian clock. (medindia.net)
  • Using optogenetics, a technique that uses light to activate or deactivate targeted brain cells - to map brain circuitry revealed two parallel pathways between the biological clock and a population of neurons in a sub-region of the hypothalamus (called the VMHvl) known to cause violent attacks when stimulated in male mice. (medindia.net)
  • Normal Clock ∆19/∆19 mice had neurons with smaller apical dendrite trees in the medial prefrontal cortex (mPFC), and hippocampus, showed impaired visual-spatial memory, and exhibited lower cerebrovascular myogenic tone, versus wild types (WT). (nature.com)
  • The research focuses on GABA signaling because its role in the SCN is prominent, not well understood, and recent advances by the three participating investigators will enable a complete and careful dissection of the role of this common neurotransmitter with synapse-level resolution across large arrays of circadian neurons. (simtk.org)
  • I believe for systems biology approaches to succeed it is crucial that models must be made easily accessible to experimentalists, which is the case in this field (eg Circadian Modelling ). (nature.com)
  • The coordination of the clock and cell division through cell cycle checkpoints, supports the clock s integral role in basic cell biology, conclude the researchers. (rxpgnews.com)
  • Their research "gave a lot of recognition to the field of circadian biology," Scheer said. (asbmb.org)
  • Taken together, these results show that it is possible to detect clock gene interactions associated with human circadian phenotypes and bring an innovative idea of building a clock gene variation map that may be applied to human circadian biology. (scielo.br)
  • A circadian clock optimizes many aspects of plant biology relative to the light/dark cycle. (nih.gov)
  • The circadian clock synchronizes internal biology with the external daily cycle of light and temperature. (plantphysiol.org)
  • Clearly oscillations in mRNA abundance cannot account for all circadian-mediated biology because both posttranscriptional and posttranslational regulation have been shown to play a major role in clock function (Lee et al. (plantphysiol.org)
  • To examine the influence of the circadian clock on immunity at the molecular level, Fikrig's group conducted a series of murine experiments in which they demonstrated the variation of TLR9 expression and daily peaks in clock gene expression. (medpagetoday.com)
  • These results are consistent with the idea that ovarian steroid levels during the estrous cycle have a modulating influence of clock gene expression in the uterus. (frontiersin.org)
  • These results correlated with respective gene expression in liver and the serum markers of circadian function. (diabetesjournals.org)
  • The comparison of the Period gene expression patterns under different conditions as well as their regulation after certain hormonal treatments can give us some clues to understand the molecular interactions of the HPA axis and the circadian clock system, and their interplay in the development of human diseases. (uni-trier.de)
  • Rhythmic gene expression underlies many of these complex circadian rhythms. (plantphysiol.org)
  • All levels of biological organization within an organism, from gene expression to immune function, behaviour and seasonal patterns of reproduction are subject to regulation by the clock [ 1 ]. (royalsocietypublishing.org)
  • Here we report variation in circadian clock gene expression patterns in the parasitoid wasp Nasonia vitripennis . (amnat.org)
  • These results point towards adaptive latitudinal clock-gene expression differences and to a key role of per in the timing of photoperiodic diapause induction of N. vitripennis . (amnat.org)
  • talks.cam : Predicting the pleiotropic effects of circadian timing, from clock gene expression to biomass. (cam.ac.uk)
  • We've shown that the circadian clock in the kidney plays an important role in different metabolic and homeostatic processes at both the intra-renal and systemic levels and is involved in drug disposition. (medicalnewstoday.com)
  • Until now, it has never been shown that the circadian system is crucial to learning and memory. (stanford.edu)
  • The researchers used different approaches to disrupt the circadian clocks of individual mice. (redorbit.com)
  • The light disrupted their circadian cycles and the mice were stuck in an inactive/fasting phase. (redorbit.com)
  • In another experiment, they used genetically modified mice that lacked the gene needed for proper biological clock function. (redorbit.com)
  • Note that this study demonstrates that the circadian molecular clock controls the expression and function of toll-like receptor 9 (TLR9), which in turn modulates the response to vaccination and sepsis models in mice. (medpagetoday.com)
  • Using high-efficiency N -ethyl- N -nitrosourea mutagenesis, we isolated the first single-gene mutation that affects circadian rhythms in mice. (hhmi.org)
  • Using a combined approach of positional cloning and transgenic (functional) rescue of the Clock mutation in mice, we found that the Clock gene encodes a novel member of the basic helix-loop-helix (bHLH)-PAS family of transcription factors. (hhmi.org)
  • The effect of different photoperiods in circadian rhythms of per3 knockout mice. (nih.gov)
  • When those mice were given GABA antagonists, their ability to learn was restored, suggesting a possible link with their circadian system. (stanford.edu)
  • Laboratory animals-rats, mice and hamsters-whose circadian systems have been disabled as part of a study typically live long and healthy lives. (stanford.edu)
  • Scientists have now investigated exactly how the mitochondrial network interacts with our internal biological clock by using a combination of in vitro models and clock-deficient mice or mice with impaired mitochondrial fission. (medindia.net)
  • A key study to draw attention to the potential role of the circadian clock and pregnancy was that of Miller et al (2004), who reported that pregnant mice lacking the functional Clock gene (ClockΔ19) had prolonged and non-productive parturition, suggestive of a role for circadian clocks in the parturition event. (frontiersin.org)
  • Lacking a gene in the liver that drives the circadian clock was sufficient to not only change the resiliency of these male mice to weight loss during restricted feeding but also to change their gut microbiome," said senior author Dr. Kjersti Aagaard professor of obstetrics and gynecology at Baylor. (eurekalert.org)
  • Importantly, deletion of Reverba inverted circadian liver GC sensitivity and protected mice from hepatosteatosis induced by chronic GC administration. (jci.org)
  • However, the liver clock of type-1 diabetes model mice was observed to be entrained by scheduled feeding, suggesting that insulin is not necessary for entrainment in the liver clock by feeding. (waseda.jp)
  • Then, these profiles will be used to compare with the ones derived from one strain of tissue-specific mutant mice, which is generated from bone marrow transplantation and carries with normal immune clock but mutated SCN clock ( SCN-mPer1 -/- /mPer2 -/- ). (dana.org)
  • Here we test whether environmental disruption of circadian rhythms, using repeated shifts of the light:dark (LD) cycle, adversely affects reproductive success in mice. (nih.gov)
  • Repeated shifting of the LD cycle, which disrupts endogenous circadian timekeeping, dramatically reduces pregnancy success in mice. (nih.gov)
  • That idea could be easily tested by giving mice resveratrol, a SIRT1-boosting ingredient found in red wine, and examining its effects on clock function, he added. (sciencecodex.com)
  • Finally, in mice lacking SIRT1 only in the liver, they found evidence that SIRT1 normally contributes to circadian control in a living animal. (sciencecodex.com)
  • Intriguingly, adaptations to neuron morphology, memory, and cerebrovascular tone occurred in differing magnitude and direction between Clock ∆19/∆19 and WT mice, ultimately converging in HF. (nature.com)
  • Indeed, the Penn researchers could also cause obesity in normal mice by replicating the altered pattern of food consumption observed in mice with a broken clock in their fat cells. (anabolicminds.com)
  • Knockout mice for Per1, Per2, Per3, Cry1, Cry2, and Clock (gifts of D. Weaver, A. Sancar, and S. Reppert) were crossed with luciferase reporter strains and molecular circadian rhythms were measured in retinal whole-mounts as in Ruan et al. (arvojournals.org)
  • Retinas from Per1-/-, Cry1-/-, and Clock-/- mice were arrhythmic or showed severely disrupted gene cycling, whereas retinas from Per2-/-, Per3-/- and Cry2-/- mice were robustly rhythmic. (arvojournals.org)
  • Takahashi and colleagues also noted that the penetrance of the clock mutant phenotype (that is, the fraction of mice in which these traits were evident) was much higher in some strains than in others. (elifesciences.org)
  • The capacity of immortalized cells to generate circadian rhythms in the expression of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) was also examined concurrently ( 12 ) because these neurotrophins are found in the SCN and BDNF levels oscillate on a circadian basis in vivo ( 13 , 14 ). (sciencemag.org)
  • Dartmouth researchers have found evidence of two circadian clocks working within the same tissue of the plant Arabidopsis thaliana , a flowering plant often used in genetic studies. (dartmouth.edu)
  • It is also of note that Dodd et al use an existing mathematical model of the Arabidopsis clock ( Locke et al, Mol Syst Biol, 2005 ) to frame the expected effects of their predicted feedback loop. (nature.com)
  • It is exciting to see how the Arabidopsis clock community has responded to this work. (nature.com)
  • To determine the extent to which the circadian clock controls transcription in Arabidopsis, we used in vivo enhancer trapping. (plantphysiol.org)
  • In Arabidopsis thaliana, establishment of the circadian period relies on targeted degradation of TIMING OF CAB EXPRESSION 1 (TOC1) by the 26S proteasome. (washington.edu)
  • Our ultimate aim is to understand both this artificial selection and the natural selection of the clock gene circuit in the model plant species, Arabidopsis thaliana. (cam.ac.uk)
  • The molecular response of an organism -- be it mouse or man -- to pathogenic invasion is controlled by circadian rhythms, researchers found. (medpagetoday.com)
  • Ruby said researchers have known since the early '70s that the circadian system modulates learning in humans and other animals, but no one knew what the effect would be on learning if the system was completely wiped out. (stanford.edu)
  • Researchers at Baylor College of Medicine have discovered that changing the circadian clock in mouse liver can alter how the body responds to diet and also change the microbes living in the digestive track. (eurekalert.org)
  • In this study the researchers explored whether changing the circadian clock would affect the microbiome. (eurekalert.org)
  • By exposing rats to a very short day/night schedule - a regimen that effectively pushes the limits of the SCN s ability to set the clock to day length - researchers have discovered within the SCN two sub-clocks that normally oscillate in unison, but can become disconnected from one another as a result of artificial day/night cycles. (innovations-report.com)
  • Mar. 29, 2018- Human tumors appear to have a broken circadian clock, researchers at Vanderbilt University Medical Center report in the journal PeerJ. (vanderbilt.edu)
  • It allowed researchers to develop tools to study cause and effect to manipulate particular core clock molecules. (asbmb.org)
  • This is the first demonstration of a circadian clock in a prokaryote outside the phylum Cyanobacteria, and the researchers' findings suggest that the cyanobacterial and E. aerogenes clocks share common evolutionary ancestors. (sciforums.com)
  • A study by Vanderbilt University researchers published online Feb. 17 by the journal Nature provides compelling new evidence that at least some species can alter the way that their biological clocks function by using different "synonyms" that exist in the genetic code. (bio-medicine.org)
  • Work by researchers at the universities of Aberdeen and Nottingham suggest an anatomical basis for the adaptation of the mammalian circadian clock to changing day-length. (phys.org)
  • Using a clever combination of genetic and biochemical tools researchers have shown that a transcription factor called USF1 has a central role in determining how mutations of the Clock gene manifest themselves in the behaviour of different mouse strains. (elifesciences.org)
  • The data suggest that circadian clock-targeted agents could treat a wide range of cancers with few side effects, the researchers say. (acs.org)
  • An appropriate way to determine the adaptive significance of circadian programs would be to examine the reproductive fitness of mutants whose circadian clockwork is altered. (pnas.org)
  • But hamsters whose circadian system was disabled by a new technique Ruby and his colleagues developed consistently failed to demonstrate the same evidence of remembering their environment as hamsters with normally functioning circadian systems. (stanford.edu)
  • The mammalian circadian timing system consists of a central pacemaker in the brain that synchronizes subsidiary oscillators in virtually all cells of the body. (weizmann.ac.il)
  • Their work, reported June 29 in Science Express, the advance electronic publication of Science, implies a protective dimension for the biological clock in addition to its pacemaker functions that play such a sweeping role in the rhythms and activities of life. (rxpgnews.com)
  • Scientists found that a certain class of bacteria found in the human gut, Enterobacter aerogenes, expresses circadian patterns because of its sensitivity to melatonin, the hormone produced at night and stimulating sleep. (sciforums.com)
  • The SCN maintains control across the body by synchronizing "slave oscillators", which exhibit their own near-24-hour rhythms and control circadian phenomena in local tissue. (wikipedia.org)
  • See section "regulation of circadian oscillators" below for more details. (wikipedia.org)
  • Buhr ED, Yoo SH, Takahashi JS (2010) Temperature as a universal resetting cue for mammalian circadian oscillators. (springer.com)
  • The results add to a growing awareness that it is a network of multiple oscillators, not only throughout the brain and body but also within the SCN itself, that underlies the workings of the circadian timing system. (innovations-report.com)
  • One idea for which evidence has accumulated is that circadian clocks contain coupled "morning" and "evening" oscillators that are separately synchronized to dawn and dusk. (phys.org)
  • The research has the potential to be highly transformative by both advancing the multiscale modeling of coupled oscillators/complex networks and by fundamentally changing our understanding of GABA signaling in circadian timekeeping and potentially in other brain regions. (simtk.org)