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1.
Nat Commun ; 10(1): 3503, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409809

RESUMO

Excessive daytime sleepiness (EDS) affects 10-20% of the population and is associated with substantial functional deficits. Here, we identify 42 loci for self-reported daytime sleepiness in GWAS of 452,071 individuals from the UK Biobank, with enrichment for genes expressed in brain tissues and in neuronal transmission pathways. We confirm the aggregate effect of a genetic risk score of 42 SNPs on daytime sleepiness in independent Scandinavian cohorts and on other sleep disorders (restless legs syndrome, insomnia) and sleep traits (duration, chronotype, accelerometer-derived sleep efficiency and daytime naps or inactivity). However, individual daytime sleepiness signals vary in their associations with objective short vs long sleep, and with markers of sleep continuity. The 42 sleepiness variants primarily cluster into two predominant composite biological subtypes - sleep propensity and sleep fragmentation. Shared genetic links are also seen with obesity, coronary heart disease, psychiatric diseases, cognitive traits and reproductive ageing.

2.
Nat Commun ; 10(1): 1100, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846698

RESUMO

Sleep is an essential state of decreased activity and alertness but molecular factors regulating sleep duration remain unknown. Through genome-wide association analysis in 446,118 adults of European ancestry from the UK Biobank, we identify 78 loci for self-reported habitual sleep duration (p < 5 × 10-8; 43 loci at p < 6 × 10-9). Replication is observed for PAX8, VRK2, and FBXL12/UBL5/PIN1 loci in the CHARGE study (n = 47,180; p < 6.3 × 10-4), and 55 signals show sign-concordant effects. The 78 loci further associate with accelerometer-derived sleep duration, daytime inactivity, sleep efficiency and number of sleep bouts in secondary analysis (n = 85,499). Loci are enriched for pathways including striatum and subpallium development, mechanosensory response, dopamine binding, synaptic neurotransmission and plasticity, among others. Genetic correlation indicates shared links with anthropometric, cognitive, metabolic, and psychiatric traits and two-sample Mendelian randomization highlights a bidirectional causal link with schizophrenia. This work provides insights into the genetic basis for inter-individual variation in sleep duration implicating multiple biological pathways.


Assuntos
Loci Gênicos , Sono/genética , Acelerometria , Adulto , Idoso , Grupo com Ancestrais do Continente Europeu , Feminino , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Autorrelato , Sono/fisiologia , Reino Unido
3.
FASEB J ; 33(5): 6226-6238, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30794439

RESUMO

Pulmonary airway epithelial cells (AECs) form a critical interface between host and environment. We investigated the role of the circadian clock using mice bearing targeted deletion of the circadian gene brain and muscle ARNT-like 1 (Bmal1) in AECs. Pulmonary neutrophil infiltration, biomechanical function, and responses to influenza infection were all disrupted. A circadian time-series RNA sequencing study of laser-captured AECs revealed widespread disruption in genes of the core circadian clock and output pathways regulating cell metabolism (lipids and xenobiotics), extracellular matrix, and chemokine signaling, but strikingly also the gain of a novel rhythmic transcriptome in Bmal1-targeted cells. Many of the rhythmic components were replicated in primary AECs cultured in air-liquid interface, indicating significant cell autonomy for control of pulmonary circadian physiology. Finally, we found that metabolic cues dictate phasing of the pulmonary clock and circadian responses to immunologic challenges. Thus, the local circadian clock in AECs is vital in lung health by coordinating major cell processes such as metabolism and immunity.-Zhang, Z. Hunter, L., Wu, G., Maidstone, R., Mizoro, Y., Vonslow, R., Fife, M., Hopwood, T., Begley, N., Saer, B., Wang, P., Cunningham, P., Baxter, M., Durrington, H., Blaikley, J. F., Hussell, T., Rattray, M., Hogenesch, J. B., Gibbs, J., Ray, D. W., Loudon, A. S. I. Genome-wide effect of pulmonary airway epithelial cell-specific Bmal1 deletion.

4.
Nat Genet ; 51(3): 387-393, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30804566

RESUMO

Insomnia is a common disorder linked with adverse long-term medical and psychiatric outcomes. The underlying pathophysiological processes and causal relationships of insomnia with disease are poorly understood. Here we identified 57 loci for self-reported insomnia symptoms in the UK Biobank (n = 453,379) and confirmed their effects on self-reported insomnia symptoms in the HUNT Study (n = 14,923 cases and 47,610 controls), physician-diagnosed insomnia in the Partners Biobank (n = 2,217 cases and 14,240 controls), and accelerometer-derived measures of sleep efficiency and sleep duration in the UK Biobank (n = 83,726). Our results suggest enrichment of genes involved in ubiquitin-mediated proteolysis and of genes expressed in multiple brain regions, skeletal muscle, and adrenal glands. Evidence of shared genetic factors was found between frequent insomnia symptoms and restless legs syndrome, aging, and cardiometabolic, behavioral, psychiatric, and reproductive traits. Evidence was found for a possible causal link between insomnia symptoms and coronary artery disease, depressive symptoms, and subjective well-being.


Assuntos
Predisposição Genética para Doença/genética , Distúrbios do Início e da Manutenção do Sono/genética , Sono/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteólise , Autorrelato , Ubiquitina/genética
6.
Thorax ; 2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30301818

RESUMO

The importance of circadian factors in managing patients is poorly understood. We present two retrospective cohort studies showing that lungs reperfused between 4 and 8 AM have a higher incidence (OR 1.12; 95% CI 1.03 to 1.21; p=0.01) of primary graft dysfunction (PGD) in the first 72 hours after transplantation. Cooling of the donor lung, occurring during organ preservation, shifts the donor circadian clock causing desynchrony with the recipient. The clock protein REV-ERBα directly regulates PGD biomarkers explaining this circadian regulation while also allowing them to be manipulated with synthetic REV-ERB ligands.

8.
FASEB J ; : fj201800026RR, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29965797

RESUMO

The circadian clock is a critical regulator of immune function. We recently highlighted a role for the circadian clock in a mouse model of pulmonary inflammation. The epithelial clock protein Bmal1 was required to regulate neutrophil recruitment in response to inflammatory challenge. Bmal1 regulated glucocorticoid receptor (GR) recruitment to the neutrophil chemokine, CXC chemokine ligand 5 (CXCL5), providing a candidate mechanism. We now show that clock control of pulmonary neutrophilia persists without rhythmic glucocorticoid availability. Epithelial GR-null mice had elevated expression of proinflammatory chemokines in the lung under homeostatic conditions. However, deletion of GR in the bronchial epithelium blocked rhythmic CXCL5 production, identifying GR as required to confer circadian control to CXCL5. Surprisingly, rhythmic pulmonary neutrophilia persisted, despite nonrhythmic CXCL5 responses, indicating additional circadian control mechanisms. Deletion of GR in myeloid cells alone did not prevent circadian variation in pulmonary neutrophilia and showed reduced neutrophilic inflammation in response to dexamethasone treatment. These new data show GR is required to confer circadian control to some inflammatory chemokines, but that this alone is insufficient to prevent circadian control of neutrophilic inflammation in response to inhaled LPS, with additional control mechanisms arising in the myeloid cell lineage.-Ince, L. M., Zhang, Z., Beesley, S., Vonslow, R. M., Saer, B. R., Matthews, L. C., Begley, N., Gibbs, J. E., Ray, D. W., Loudon, A. S. I. Circadian variation in pulmonary inflammatory responses is independent of rhythmic glucocorticoid signaling in airway epithelial cells.

9.
Sci Rep ; 8(1): 3782, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491349

RESUMO

Resistance to the intestinal parasitic helminth Trichuris muris requires T-helper 2 (TH2) cellular and associated IgG1 responses, with expulsion typically taking up to 4 weeks in mice. Here, we show that the time-of-day of the initial infection affects efficiency of worm expulsion, with strong TH2 bias and early expulsion in morning-infected mice. Conversely, mice infected at the start of the night show delayed resistance to infection, and this is associated with feeding-driven metabolic cues, such that feeding restriction to the day-time in normally nocturnal-feeding mice disrupts parasitic expulsion kinetics. We deleted the circadian regulator BMAL1 in antigen-presenting dendritic cells (DCs) in vivo and found a loss of time-of-day dependency of helminth expulsion. RNAseq analyses revealed that IL-12 responses to worm antigen by circadian-synchronised DCs were dependent on BMAL1. Therefore, we find that circadian machinery in DCs contributes to the TH1/TH2 balance, and that environmental, or genetic perturbation of the DC clock results in altered parasite expulsion kinetics.

10.
Nat Commun ; 8(1): 417, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900189

RESUMO

Most organisms use internal biological clocks to match behavioural and physiological processes to specific phases of the day-night cycle. Central to this is the synchronisation of internal processes across multiple organ systems. Environmental desynchrony (e.g. shift work) profoundly impacts human health, increasing cardiovascular disease and diabetes risk, yet the underlying mechanisms remain unclear. Here, we characterise the impact of desynchrony between the internal clock and the external light-dark (LD) cycle on mammalian physiology. We reveal that even under stable LD environments, phase misalignment has a profound effect, with decreased metabolic efficiency and disrupted cardiac function including prolonged QT interval duration. Importantly, physiological dysfunction is not driven by disrupted core clock function, nor by an internal desynchrony between organs, but rather the altered phase relationship between the internal clockwork and the external environment. We suggest phase misalignment as a major driver of pathologies associated with shift work, chronotype and social jetlag.The misalignment between internal circadian rhythm and the day-night cycle can be caused by genetic, behavioural and environmental factors, and may have a profound impact on human physiology. Here West et al. show that desynchrony between the internal clock and the external environment alter metabolic parameters and cardiac function in mice.


Assuntos
Metabolismo Energético/fisiologia , Coração/fisiopatologia , Fotoperíodo , Animais , Relógios Biológicos/fisiologia , Eletrocardiografia , Regulação da Expressão Gênica , Frequência Cardíaca , Masculino , Camundongos Endogâmicos C57BL
11.
FASEB J ; 30(11): 3759-3770, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27488122

RESUMO

There is strong diurnal variation in the symptoms and severity of chronic inflammatory diseases, such as rheumatoid arthritis. In addition, disruption of the circadian clock is an aggravating factor associated with a range of human inflammatory diseases. To investigate mechanistic links between the biological clock and pathways underlying inflammatory arthritis, mice were administered collagen (or saline as a control) to induce arthritis. The treatment provoked an inflammatory response within the limbs, which showed robust daily variation in paw swelling and inflammatory cytokine expression. Inflammatory markers were significantly repressed during the dark phase. Further work demonstrated an active molecular clock within the inflamed limbs and highlighted the resident inflammatory cells, fibroblast-like synoviocytes (FLSs), as a potential source of the rhythmic inflammatory signal. Exposure of mice to constant light disrupted the clock in peripheral tissues, causing loss of the nighttime repression of local inflammation. Finally, the results show that the core clock proteins cryptochrome (CRY) 1 and 2 repressed inflammation within the FLSs, and provide novel evidence that a CRY activator has anti-inflammatory properties in human cells. We conclude that under chronic inflammatory conditions, the clock actively represses inflammatory pathways during the dark phase. This interaction has exciting potential as a therapeutic avenue for treatment of inflammatory disease.-Hand, L. E., Hopwood, T. W., Dickson, S. H., Walker, A. L., Loudon, A. S. I., Ray, D. W., Bechtold, D. A., Gibbs, J. E. The circadian clock regulates inflammatory arthritis.


Assuntos
Artrite Reumatoide/metabolismo , Proteínas CLOCK/metabolismo , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Animais , Artrite Reumatoide/terapia , Proteínas CLOCK/genética , Modelos Animais de Doenças , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/terapia , Masculino , Camundongos
12.
Curr Biol ; 26(14): 1880-6, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27374340

RESUMO

Transcriptional-translational feedback loops (TTFLs) are a conserved molecular motif of circadian clocks. The principal clock in mammals is the suprachiasmatic nucleus (SCN) of the hypothalamus. In SCN neurons, auto-regulatory feedback on core clock genes Period (Per) and Cryptochrome (Cry) following nuclear entry of their protein products is the basis of circadian oscillation [1, 2]. In Drosophila clock neurons, the movement of dPer into the nucleus is subject to a circadian gate that generates a delay in the TTFL, and this delay is thought to be critical for oscillation [3, 4]. Analysis of the Drosophila clock has strongly influenced models of the mammalian clock, and such models typically infer complex spatiotemporal, intracellular behaviors of mammalian clock proteins. There are, however, no direct measures of the intracellular behavior of endogenous circadian proteins to support this: dynamic analyses have been limited and often have no circadian dimension [5-7]. We therefore generated a knockin mouse expressing a fluorescent fusion of native PER2 protein (PER2::VENUS) for live imaging. PER2::VENUS recapitulates the circadian functions of wild-type PER2 and, importantly, the behavior of PER2::VENUS runs counter to the Drosophila model: it does not exhibit circadian gating of nuclear entry. Using fluorescent imaging of PER2::VENUS, we acquired the first measures of mobility, molecular concentration, and localization of an endogenous circadian protein in individual mammalian cells, and we showed how the mobility and nuclear translocation of PER2 are regulated by casein kinase. These results provide new qualitative and quantitative insights into the cellular mechanism of the mammalian circadian clock.


Assuntos
Relógios Circadianos/genética , Camundongos/genética , Proteínas Circadianas Period/genética , Núcleo Supraquiasmático/metabolismo , Animais , Proteínas Circadianas Period/metabolismo
13.
J Leukoc Biol ; 99(4): 549-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26856993

RESUMO

Circadian rhythms regulate changes in physiology, allowing organisms to respond to predictable environmental demands varying over a 24 h period. A growing body of evidence supports a key role for the circadian clock in the regulation of immune functions and inflammatory responses, which influence the understanding of infections and inflammatory diseases and their treatment. A variety of experimental methods have been used to assess the complex bidirectional crosstalk between the circadian clock and inflammation. In this review, we summarize the organization of the molecular clock, experimental methods used to study circadian rhythms, and both the inflammatory and immune consequences of circadian disturbance.


Assuntos
Relógios Circadianos/imunologia , Modelos Animais de Doenças , Animais , Humanos , Inflamação/imunologia , Inflamação/patologia
14.
Proc Natl Acad Sci U S A ; 113(3): 686-91, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26715747

RESUMO

Circadian rhythms with an endogenous period close to or equal to the natural light-dark cycle are considered evolutionarily adaptive ("circadian resonance hypothesis"). Despite remarkable insight into the molecular mechanisms driving circadian cycles, this hypothesis has not been tested under natural conditions for any eukaryotic organism. We tested this hypothesis in mice bearing a short-period mutation in the enzyme casein kinase 1ε (tau mutation), which accelerates free-running circadian cycles. We compared daily activity (feeding) rhythms, survivorship, and reproduction in six replicate populations in outdoor experimental enclosures, established with wild-type, heterozygous, and homozygous mice in a Mendelian ratio. In the release cohort, survival was reduced in the homozygote mutant mice, revealing strong selection against short-period genotypes. Over the course of 14 mo, the relative frequency of the tau allele dropped from initial parity to 20%. Adult survival and recruitment of juveniles into the population contributed approximately equally to the selection for wild-type alleles. The expression of activity during daytime varied throughout the experiment and was significantly increased by the tau mutation. The strong selection against the short-period tau allele observed here contrasts with earlier studies showing absence of selection against a Period 2 (Per2) mutation, which disrupts internal clock function, but does not change period length. These findings are consistent with, and predicted by the theory that resonance of the circadian system plays an important role in individual fitness.


Assuntos
Relógios Circadianos/genética , Mutação/genética , Seleção Genética , Envelhecimento/genética , Alelos , Animais , Caseína Quinase I/genética , Ritmo Circadiano/genética , Comportamento Alimentar , Feminino , Frequência do Gene/genética , Genótipo , Masculino , Camundongos Endogâmicos C57BL , Análise de Sobrevida
15.
Curr Biol ; 25(20): 2651-62, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26412130

RESUMO

Persistent free-running circannual (approximately year-long) rhythms have evolved in animals to regulate hormone cycles, drive metabolic rhythms (including hibernation), and time annual reproduction. Recent studies have defined the photoperiodic input to this rhythm, wherein melatonin acts on thyrotroph cells of the pituitary pars tuberalis (PT), leading to seasonal changes in the control of thyroid hormone metabolism in the hypothalamus. However, seasonal rhythms persist in constant conditions in many species in the absence of a changing photoperiod signal, leading to the generation of circannual cycles. It is not known which cells, tissues, and pathways generate these remarkable long-term rhythmic processes. We show that individual PT thyrotrophs can be in one of two binary states reflecting either a long (EYA3(+)) or short (CHGA(+)) photoperiod, with the relative proportion in each state defining the phase of the circannual cycle. We also show that a morphogenic cycle driven by the PT leads to extensive re-modeling of the PT and hypothalamus over the circannual cycle. We propose that the PT may employ a recapitulated developmental pathway to drive changes in morphology of tissues and cells. Our data are consistent with the hypothesis that the circannual timer may reside within the PT thyrotroph and is encoded by a binary switch timing mechanism, which may regulate the generation of circannual neuroendocrine rhythms, leading to dynamic re-modeling of the hypothalamic interface. In summary, the PT-ventral hypothalamus now appears to be a prime structure involved in long-term rhythm generation.


Assuntos
Relógios Circadianos , Fotoperíodo , Ovinos/fisiologia , Tireotrofos/fisiologia , Animais , Masculino
16.
Diabetes ; 64(1): 128-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25190567

RESUMO

Obesity is a major risk factor for metabolic disease, with white adipose tissue (WAT) inflammation emerging as a key underlying pathology. We detail that mice lacking Reverbα exhibit enhanced fat storage without the predicted increased WAT inflammation or loss of insulin sensitivity. In contrast to most animal models of obesity and obese human patients, Reverbα(-/-) mice exhibit elevated serum adiponectin levels and increased adiponectin secretion from WAT explants in vitro, highlighting a potential anti-inflammatory role of this adipokine in hypertrophic WAT. Indeed, adiponectin was found to suppress primary macrophage responses to lipopolysaccharide and proinflammatory fatty acids, and this suppression depended on glycogen synthase kinase 3ß activation and induction of A20. Attenuated inflammatory responses in Reverbα(-/-) WAT depots were associated with tonic elevation of A20 protein and ex vivo shown to depend on A20. We also demonstrate that adipose A20 expression in obese human subjects exhibits a negative correlation with measures of insulin sensitivity. Furthermore, bariatric surgery-induced weight loss was accompanied by enhanced WAT A20 expression, which is positively correlated with increased serum adiponectin and improved metabolic and inflammatory markers, including C-reactive protein. The findings identify A20 as a mediator of adiponectin anti-inflammatory action in WAT and a potential target for mitigating obesity-related pathology.


Assuntos
Adiponectina/metabolismo , Cisteína Endopeptidases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Nucleares/metabolismo , Obesidade/metabolismo , Paniculite/metabolismo , Adiponectina/genética , Adiponectina/imunologia , Tecido Adiposo Branco/citologia , Tecido Adiposo Branco/imunologia , Tecido Adiposo Branco/metabolismo , Animais , Células Cultivadas , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/imunologia , Proteínas de Ligação a DNA/imunologia , Dieta Hiperlipídica , Metabolismo Energético/fisiologia , Feminino , Expressão Gênica/imunologia , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Resistência à Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Knockout , Proteínas Nucleares/imunologia , Obesidade/imunologia , Paniculite/imunologia , RNA Interferente Pequeno/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa
17.
Curr Biol ; 24(6): R232-4, 2014 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-24650909

RESUMO

Severe noise can cause permanent hearing damage. A recent study now shows that the capacity to recover from noise damage varies with time of day, driven by circadian clock control of a nerve growth factor (BDNF) in the inner ear.


Assuntos
Ritmo Circadiano/fisiologia , Cóclea/fisiologia , Ruído/efeitos adversos , Proteínas Quinases/fisiologia , Animais , Masculino
18.
Curr Biol ; 24(7): 766-73, 2014 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-24656826

RESUMO

Many aspects of mammalian physiology are driven through the coordinated action of internal circadian clocks. Clock speed (period) and phase (temporal alignment) are fundamental to an organism's ability to synchronize with its environment. In humans, lifestyles that disturb these clocks, such as shift work, increase the incidence of diseases such as cancer and diabetes. Casein kinases 1δ and ε are closely related clock components implicated in period determination. However, CK1δ is so dominant in this regard that it remains unclear what function CK1ε normally serves. Here, we reveal that CK1ε dictates how rapidly the clock is reset by environmental stimuli. Genetic disruption of CK1ε in mice enhances phase resetting of behavioral rhythms to acute light pulses and shifts in light cycle. This impact of CK1ε targeting is recapitulated in isolated brain suprachiasmatic nucleus and peripheral (lung) clocks during NMDA- or temperature-induced phase shift in association with altered PERIOD (PER) protein dynamics. Importantly, accelerated re-entrainment of the circadian system in vivo and in vitro can be achieved in wild-type animals through pharmacological inhibition of CK1ε. These studies therefore reveal a role for CK1ε in stabilizing the circadian clock against phase shift and highlight it as a novel target for minimizing physiological disturbance in shift workers.


Assuntos
Relógios Circadianos/fisiologia , Animais , Caseína Quinase Iépsilon/genética , Caseína Quinase Iépsilon/metabolismo , Caseína Quinase Iépsilon/fisiologia , Relógios Circadianos/genética , Relógios Circadianos/efeitos da radiação , Ritmo Circadiano/fisiologia , Masculino , Camundongos , Fotoperíodo , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiologia
19.
Thorax ; 69(1): 90-2, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23704227

RESUMO

It is characteristic of asthma that symptoms worsen overnight, particularly in the early hours of the morning. Nocturnal symptoms in asthma are common and are an important indicator for escalation of treatment. An extensive body of research has demonstrated that nocturnal symptoms of cough and dyspnea are accompanied by circadian variations in airway inflammation and physiologic variables, including airflow limitation and airways hyper-responsiveness. The molecular apparatus that underpins circadian variations, controlled by so called 'clock' genes, has recently been characterised. Clock genes control circadian rhythms both centrally, in the suprachiasmatic nucleus of the brain and peripherally, within every organ of the body. Here, we will discuss how clock genes regulate circadian rhythms. We will focus particularly on the peripheral lung clock and the peripheral immune clock and discuss how these might relate to both the pathogenesis and treatment of asthma.


Assuntos
Asma/fisiopatologia , Relógios Circadianos/genética , Pulmão/fisiopatologia , Fatores de Transcrição ARNTL/genética , Antiasmáticos/administração & dosagem , Broncoscopia , Proteínas CLOCK/genética , Cronoterapia Farmacológica , Humanos
20.
Nucleic Acids Res ; 41(18): 8515-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23887939

RESUMO

The glucocorticoid receptor (GR) is a ligand activated transcription factor, serving to regulate both energy metabolism and immune functions. Factors that influence cellular sensitivity to glucocorticoids (GC) are therefore of great interest. The N-terminal of the GR contains numerous potential proline-directed phosphorylation sites, some of which can regulate GR transactivation. Unrestricted proline isomerisation can be inhibited by adjacent serine phosphorylation and requires a prolyl isomerise, Pin1. Pin1 therefore determines the functional outcome of proline-directed kinases acting on the GR, as cis/trans isomers are distinct pools with different interacting proteins. We show that Pin1 mediates GR transactivation, but not GR trans-repression. Two N-terminal GR serines, S203 and S211, are targets for Pin1 potentiation of GR transactivation, establishing a direct link between Pin1 and the GR. We also demonstrate GC-activated co-recruitment of GR and Pin1 to the GILZ gene promoter. The Pin1 effect required both its WW and catalytic domains, and GR recruitment to its GRE was Pin1-dependent. Therefore, Pin1 is a selective regulator of GR transactivation, acting through N-terminal phospho-serine residues to regulate GR recruitment to its target sites in the genome. As Pin1 is dysregulated in disease states, this interaction may contribute to altered GC action in inflammatory conditions.


Assuntos
Peptidilprolil Isomerase/fisiologia , Receptores de Glucocorticoides/metabolismo , Ativação Transcricional , Linhagem Celular , Dexametasona/farmacologia , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Coativador 3 de Receptor Nuclear/fisiologia , Peptidilprolil Isomerase/antagonistas & inibidores , Fosforilação , Regiões Promotoras Genéticas , Estabilidade Proteica , Receptores de Glucocorticoides/química , Proteínas Repressoras/metabolismo
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