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1.
PLoS Genet ; 15(11): e1008475, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710605

RESUMO

Circadian rhythms are generated by endogenous pacemakers that rely on transcriptional-translational feedback mechanisms conserved among species. In Drosophila, the stability of a key pacemaker protein PERIOD (PER) is tightly controlled by changes in phosphorylation status. A number of molecular players have been implicated in PER destabilization by promoting PER progressive phosphorylation. On the other hand, there have been few reports describing mechanisms that stabilize PER by delaying PER hyperphosphorylation. Here we report that the protein Suppressor of Ras (SUR-8) regulates circadian locomotor rhythms by stabilizing PER. Depletion of SUR-8 from circadian neurons lengthened the circadian period by about 2 hours and decreased PER abundance, whereas its overexpression led to arrhythmia and an increase in PER. Specifically SUR-8 promotes the stability of PER through phosphorylation regulation. Interestingly, downregulation of the protein phosphatase 1 catalytic subunit PP1-87B recapitulated the phenotypes of SUR-8 depletion. We found that SUR-8 facilitates interactions between PP1-87B and PER. Depletion of SUR-8 decreased the interaction of PER and PP1-87B, which supports the role of SUR-8 as a scaffold protein. Interestingly, the interaction between SUR-8 and PER is temporally regulated: SUR-8 has more binding to PER at night than morning. Thus, our results indicate that SUR-8 interacts with PP1-87B to control PER stability to regulate circadian rhythms.


Assuntos
Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Proteínas Circadianas Period/genética , Proteína Fosfatase 1/genética , Animais , Domínio Catalítico/genética , Drosophila melanogaster/genética , Neurônios/metabolismo , Fosforilação
2.
PLoS Genet ; 15(11): e1008478, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31693685

RESUMO

Circadian rhythms allow animals to coordinate behavioral and physiological processes with respect to one another and to synchronize these processes to external environmental cycles. In most animals, circadian rhythms are produced by core clock neurons in the brain that generate and transmit time-of-day signals to downstream tissues, driving overt rhythms. The neuronal pathways controlling clock outputs, however, are not well understood. Furthermore, it is unclear how the central clock modulates multiple distinct circadian outputs. Identifying the cellular components and neuronal circuitry underlying circadian regulation is increasingly recognized as a critical step in the effort to address health pathologies linked to circadian disruption, including heart disease and metabolic disorders. Here, building on the conserved components of circadian and metabolic systems in mammals and Drosophila melanogaster, we used a recently developed feeding monitor to characterize the contribution to circadian feeding rhythms of two key neuronal populations in the Drosophila pars intercerebralis (PI), which is functionally homologous to the mammalian hypothalamus. We demonstrate that thermogenetic manipulations of PI neurons expressing the neuropeptide SIFamide (SIFa) as well as mutations of the SIFa gene degrade feeding:fasting rhythms. In contrast, manipulations of a nearby population of PI neurons that express the Drosophila insulin-like peptides (DILPs) affect total food consumption but leave feeding rhythms intact. The distinct contribution of these two PI cell populations to feeding is accompanied by vastly different neuronal connectivity as determined by trans-Tango synaptic mapping. These results for the first time identify a non-clock cell neuronal population in Drosophila that regulates feeding rhythms and furthermore demonstrate dissociable control of circadian and homeostatic aspects of feeding regulation by molecularly-defined neurons in a putative circadian output hub.


Assuntos
Relógios Circadianos/genética , Drosophila melanogaster/genética , Comportamento Alimentar/fisiologia , Proteínas Circadianas Period/genética , Animais , Animais Geneticamente Modificados , Encéfalo/fisiologia , Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Jejum , Hipotálamo/metabolismo , Mamíferos/genética , Mamíferos/fisiologia , Neuroglia/fisiologia , Neurônios/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo
3.
Elife ; 82019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31613218

RESUMO

In Drosophila, ~150 neurons expressing molecular clock proteins regulate circadian behavior. Sixteen of these neurons secrete the neuropeptide Pdf and have been called 'master pacemakers' because they are essential for circadian rhythms. A subset of Pdf+ neurons (the morning oscillator) regulates morning activity and communicates with other non-Pdf+ neurons, including a subset called the evening oscillator. It has been assumed that the molecular clock in Pdf+ neurons is required for these functions. To test this, we developed and validated Gal4-UAS based CRISPR tools for cell-specific disruption of key molecular clock components, period and timeless. While loss of the molecular clock in both the morning and evening oscillators eliminates circadian locomotor activity, the molecular clock in either oscillator alone is sufficient to rescue circadian locomotor activity in the absence of the other. This suggests that clock neurons do not act in a hierarchy but as a distributed network to regulate circadian activity.


Assuntos
Relógios Circadianos/genética , Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Neurônios/metabolismo , Neuropeptídeos/genética , Proteínas Circadianas Period/genética , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Sistemas CRISPR-Cas , Comunicação Celular , Linhagem da Célula/genética , Relógios Circadianos/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Escuridão , Proteínas de Drosophila/deficiência , Drosophila melanogaster/metabolismo , Drosophila melanogaster/efeitos da radiação , Retroalimentação Fisiológica , Edição de Genes , Regulação da Expressão Gênica , Transdução de Sinal Luminoso/genética , Locomoção/genética , Locomoção/efeitos da radiação , Rede Nervosa/metabolismo , Rede Nervosa/efeitos da radiação , Neurônios/citologia , Neurônios/efeitos da radiação , Neuropeptídeos/deficiência , Proteínas Circadianas Period/deficiência , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
4.
Elife ; 82019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31613223

RESUMO

Animal circadian rhythms persist in constant darkness and are driven by intracellular transcription-translation feedback loops. Although these cellular oscillators communicate, isolated mammalian cellular clocks continue to tick away in darkness without intercellular communication. To investigate these issues in Drosophila, we assayed behavior as well as molecular rhythms within individual brain clock neurons while blocking communication within the ca. 150 neuron clock network. We also generated CRISPR-mediated neuron-specific circadian clock knockouts. The results point to two key clock neuron groups: loss of the clock within both regions but neither one alone has a strong behavioral phenotype in darkness; communication between these regions also contributes to circadian period determination. Under these dark conditions, the clock within one region persists without network communication. The clock within the famous PDF-expressing s-LNv neurons however was strongly dependent on network communication, likely because clock gene expression within these vulnerable sLNvs depends on neuronal firing or light.


Assuntos
Encéfalo/metabolismo , Relógios Circadianos/genética , Ritmo Circadiano/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica , Transdução de Sinal Luminoso/genética , Neurônios/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/deficiência , Fatores de Transcrição de Zíper de Leucina Básica/genética , Encéfalo/citologia , Encéfalo/efeitos da radiação , Sistemas CRISPR-Cas , Comunicação Celular , Linhagem da Célula/genética , Relógios Circadianos/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Escuridão , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/efeitos da radiação , Retroalimentação Fisiológica , Edição de Genes , Rede Nervosa/metabolismo , Rede Nervosa/efeitos da radiação , Neurônios/citologia , Neurônios/efeitos da radiação , Neuropeptídeos/deficiência , Neuropeptídeos/genética , Proteínas Circadianas Period/deficiência , Proteínas Circadianas Period/genética , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
5.
Endocrinology ; 160(10): 2215-2229, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398249

RESUMO

The circadian glucocorticoid (GC) rhythm is dependent on a molecular clock in the suprachiasmatic nucleus (SCN) and an adrenal clock that is synchronized by the SCN. To determine whether the adrenal clock modulates GC responses to stress, experiments used female and male Cyp11A1Cre/+::Bmal1Fl/Fl knockout [side-chain cleavage (SCC)-KO] mice, in which the core clock gene, Bmal1, is deleted in all steroidogenic tissues, including the adrenal cortex. Following restraint stress, female and male SCC-KO mice demonstrate augmented plasma corticosterone but not plasma ACTH. In contrast, following submaximal scruff stress, plasma corticosterone was elevated only in female SCC-KO mice. Adrenal sensitivity to ACTH was measured in vitro using acutely dispersed adrenocortical cells. Maximal corticosterone responses to ACTH were elevated in cells from female KO mice without affecting the EC50 response. Neither the maximum nor the EC50 response to ACTH was affected in male cells, indicating that female SCC-KO mice show a stronger adrenal phenotype. Parallel experiments were conducted using female Cyp11B2 (Aldosterone Synthase)Cre/+::Bmal1Fl/Fl mice and adrenal cortex-specific Bmal1-null (Ad-KO) mice. Plasma corticosterone was increased in Ad-KO mice following restraint or scruff stress, and in vitro responses to ACTH were elevated in adrenal cells from Ad-KO mice, replicating data from female SCC-KO mice. Gene analysis showed increased expression of adrenal genes in female SCC-KO mice involved in cell cycle control, cell adhesion-extracellular matrix interaction, and ligand receptor activity that could promote steroid production. These observations underscore a role for adrenal Bmal1 as an attenuator of steroid secretion that is most prominent in female mice.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Córtex Suprarrenal/metabolismo , Corticosterona/sangue , Glucocorticoides/metabolismo , Fatores de Transcrição ARNTL/genética , Hormônio Adrenocorticotrópico , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Feminino , Genótipo , Masculino , Camundongos , Camundongos Knockout , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Fatores Sexuais , Estresse Fisiológico
6.
Molecules ; 24(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31408938

RESUMO

Resveratrol (RES) possesses anti-inflammatory and anti-oxidant activities, and it can prevent liver lipid metabolism disorders in obese and diabetic individuals. This study elucidated the mechanisms of brain and muscle Arnt-like protein-1 (Bmal1) in the protective effects of RES against liver lipid metabolism disorders. The results indicated that RES ameliorated free fatty acid (FFA)-induced (oleic acid (OA): palmitic acid (PA) = 2:1) glycolipid metabolic disorders in hepatocytes. Simultaneously, RES partially reverted the relatively shallow daily oscillations of FFA-induced circadian clock gene transcription and protein expression in HepG2 cells. RES also attenuated FFA-triggered reactive oxygen species (ROS) secretion and restored mitochondrial membrane potential consumption, as well as the restoration of mitochondrial respiratory complex expression. This study provides compelling evidence that RES controls intracellular lipid metabolic imbalance in a Bmal1-dependent manner. Overall, RES may serve as a promising natural nutraceutical for the regulation of lipid metabolic disorders relevant to the circadian clock.


Assuntos
Fatores de Transcrição ARNTL/genética , Relógios Circadianos/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Resveratrol/farmacologia , Fatores de Transcrição ARNTL/antagonistas & inibidores , Fatores de Transcrição ARNTL/metabolismo , Animais , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relógios Circadianos/genética , Criptocromos/genética , Criptocromos/metabolismo , Regulação da Expressão Gênica , Células Hep G2 , Hepatócitos/citologia , Hepatócitos/metabolismo , Homeostase/genética , Humanos , Metabolismo dos Lipídeos/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ácido Oleico/antagonistas & inibidores , Ácido Oleico/farmacologia , Ácido Palmítico/antagonistas & inibidores , Ácido Palmítico/farmacologia , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
7.
Asian Pac J Cancer Prev ; 20(7): 2195-2201, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31350984

RESUMO

Objective: Period1 (PER1), a core circadian gene, not only modulates circadian rhythm but may also play an important role in other biological processes, including pathways involved in the proliferation and apoptosis of tumor cells. In this study, we investigated the mechanism by which the downregulated expression of PER1 promotes the apoptosis of wild-type P53 human glioma U343 cells exposed to X-rays. Methods:U343 cells were exposed to 6 mV 10 Gy X-ray irradiation after infection with an shRNA lentivirus to reduce the expression of PER1 and were analyzed by SCGE analysis, flow cytometry, qRT-PCR, and western blotting. Result: SCGE analysis revealed that compared with the controls, U343 cells expressing low levels of PER1 showed minor DNA damage when exposed to X-ray irradiation (P<0.05), and the flow cytometry assay showed lower death rates (P<0.05). RT-PCR and western blot analysis both revealed decreased expression of CHK2 and P53, which regulate DNA damage and repair via the CHK2-P53 pathway, and decreased expression of C-MYC, which is related to cell apoptosis. Conclusion:Our research suggests that PER1 may play an important role in tumor radiotherapy, which is attributable to enhanced chk2-P53 signaling and proapoptotic processes. These findings provide a new target for the clinical treatment of glioma and a reliable basis for postradiation therapy and gene therapy for glioma and other cancers.


Assuntos
Apoptose/efeitos da radiação , Quinase do Ponto de Checagem 2/metabolismo , Dano ao DNA/efeitos da radiação , Glioma/patologia , Proteínas Circadianas Period/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Quinase do Ponto de Checagem 2/genética , Ritmo Circadiano , Regulação para Baixo , Glioma/genética , Glioma/radioterapia , Humanos , Proteínas Circadianas Period/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Raios X
8.
J Agric Food Chem ; 67(32): 8735-8739, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31244204

RESUMO

The circadian clock is an intrinsic mechanism of biological adaptation to the cyclical changes of the environment. The circadian rhythm disorders affect the life activities of organisms. A variety of phytochemicals (e.g., polyphenols, flavonoids, alkaloids, and melatonin) reportedly can regulate the expression and rhythm of circadian clock genes and stabilize the internal environment. This perspective focuses on the relationship of circadian clock genes with oxidative stress, inflammatory response, and metabolic disorders and emphasizes the regulation of phytochemicals on the circadian clock. Potential mechanisms and applications of supplemental phytochemicals to improve metabolic disorders and circadian rhythm disorders are also discussed.


Assuntos
Relógios Circadianos , Doenças Metabólicas/fisiopatologia , Compostos Fitoquímicos/metabolismo , Animais , Humanos , Doenças Metabólicas/genética , Doenças Metabólicas/metabolismo , Estresse Oxidativo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo
9.
Genome Res ; 29(8): 1262-1276, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31249065

RESUMO

Organisms use endogenous clocks to adapt to the rhythmicity of the environment and to synchronize social activities. Although the circadian cycle is implicated in aging, it is unknown whether natural variation in its function contributes to differences in lifespan between populations and whether the circadian clock of specific tissues is key for longevity. We have sequenced the genomes of Drosophila melanogaster strains with exceptional longevity that were obtained via multiple rounds of selection from a parental strain. Comparison of genomic, transcriptomic, and proteomic data revealed that changes in gene expression due to intergenic polymorphisms are associated with longevity and preservation of skeletal muscle function with aging in these strains. Analysis of transcription factors differentially modulated in long-lived versus parental strains indicates a possible role of circadian clock core components. Specifically, there is higher period and timeless and lower cycle expression in the muscle of strains with delayed aging compared to the parental strain. These changes in the levels of circadian clock transcription factors lead to changes in the muscle circadian transcriptome, which includes genes involved in metabolism, proteolysis, and xenobiotic detoxification. Moreover, a skeletal muscle-specific increase in timeless expression extends lifespan and recapitulates some of the transcriptional and circadian changes that differentiate the long-lived from the parental strains. Altogether, these findings indicate that the muscle circadian clock is important for longevity and that circadian gene variants contribute to the evolutionary divergence in longevity across populations.


Assuntos
Fatores de Transcrição ARNTL/genética , Relógios Circadianos/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genoma de Inseto , Longevidade/genética , Músculo Esquelético/metabolismo , Proteínas Circadianas Period/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Evolução Biológica , Ritmo Circadiano/genética , DNA Intergênico/genética , DNA Intergênico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Genética Populacional , Genômica , Músculo Esquelético/crescimento & desenvolvimento , Proteínas Circadianas Period/metabolismo , Polimorfismo Genético , Transcriptoma , Sequenciamento Completo do Genoma
10.
Yale J Biol Med ; 92(2): 241-250, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31249485

RESUMO

Circadian clocks drive biological rhythms in physiology and behavior, providing a selective advantage by enabling organisms to synchronize to the 24 h environmental day. This process depends on light-dark transitions as the main signal that shifts the phase of the clock. In mammals, the light input reaches the master circadian clock in the hypothalamic suprachiasmatic nucleus through glutamatergic afferents from the retina, resulting in phase-shifts of the overt rhythms which depend on the time of the day at which light is applied, leading to changes in the activity of circadian core clock genes (i.e., Per1). This circadian gating of the synchronizing effect of light is dependent on the specific activation of signal transduction pathways involving several kinases acting on protein effectors. Protein phosphorylation is also an important regulatory mechanism essential for the generation and maintenance of circadian rhythms and plays a crucial role in the degradation and the appropriate turnover of PER proteins. In this work, we review the role of the main kinases implicated in the function of the master clock, with emphasis in those involved in circadian photic entrainment.


Assuntos
Relógios Circadianos/fisiologia , Transdução de Sinal Luminoso/fisiologia , Mamíferos/fisiologia , Proteínas Quinases/metabolismo , Animais , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Luz , Mamíferos/genética , Mamíferos/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Fosforilação/efeitos da radiação
11.
Nat Commun ; 10(1): 2563, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189882

RESUMO

Non-coding cis-regulatory elements are essential determinants of development, but their exact impacts on behavior and physiology in adults remain elusive. Cis-element-based transcriptional regulation is believed to be crucial for generating circadian rhythms in behavior and physiology. However, genetic evidence supporting this model is based on mutations in the protein-coding sequences of clock genes. Here, we report generation of mutant mice carrying a mutation only at the E'-box cis-element in the promoter region of the core clock gene Per2. The Per2 E'-box mutation abolishes sustainable molecular clock oscillations and renders circadian locomotor activity and body temperature rhythms unstable. Without the E'-box, Per2 messenger RNA and protein expression remain at mid-to-high levels. Our work delineates the Per2 E'-box as a critical nodal element for keeping sustainable cell-autonomous circadian oscillation and reveals the extent of the impact of the non-coding cis-element in daily maintenance of animal locomotor activity and body temperature rhythmicity.


Assuntos
Ritmo Circadiano/genética , Elementos E-Box/genética , Proteínas Circadianas Period/genética , Regiões Promotoras Genéticas/genética , Animais , Comportamento Animal/fisiologia , Temperatura Corporal/fisiologia , Células Cultivadas , Fibroblastos , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Cultura Primária de Células , RNA Mensageiro/metabolismo
12.
PLoS One ; 14(5): e0217368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31136603

RESUMO

Environmental circadian disruption (ECD), characterized by repeated or long-term disruption in environmental timing cues which require the internal circadian clock to change its phase to resynchronize with the environment, is associated with numerous serious health issues in humans. While animal and isolated cell models exist to study the effects of destabilizing the relationship between the circadian system and the environment, neither approach provides an ideal solution. Here, we developed an in vitro model which incorporates both elements of a reductionist cellular model and disruption of the clock/environment relationship using temperature as an environmental cue, as occurs in vivo. Using this approach, we have demonstrated that some effects of in vivo ECD can be reproduced using only isolated peripheral oscillators. Specifically, we report exaggerated inflammatory responses to endotoxin following repeated environmental circadian disruption in explanted spleens. This effect requires a functional circadian clock but not the master brain clock, the suprachiasmatic nucleus (SCN). Further, we report that this is a result of cumulative, rather than acute, circadian disruption as has been previously observed in vivo. Finally, such effects appear to be tissue specific as it does not occur in lung, which is less sensitive to the temperature cycles employed to induce ECD. Taken together, the present study suggests that this model could be a valuable tool for dissecting the causes and effects of circadian disruption both in isolated components of physiological systems as well as the aggregated interactions of these systems that occur in vivo.


Assuntos
Relógios Circadianos/fisiologia , Inflamação/fisiopatologia , Núcleo Supraquiasmático/fisiologia , Animais , Relógios Circadianos/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Endotoxinas/toxicidade , Meio Ambiente , Feminino , Técnicas In Vitro , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Especificidade de Órgãos , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/fisiologia , Baço/efeitos dos fármacos , Baço/fisiologia , Núcleo Supraquiasmático/efeitos dos fármacos , Temperatura Ambiente
13.
Am Nat ; 193(6): 881-896, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31094595

RESUMO

Day length (photoperiod) and temperature oscillate daily and seasonally and are important cues for season-dependent behavior. Larval diapause of the parasitoid Nasonia vitripennis is maternally induced following a certain number of days (switch point) of a given critical photoperiod (CPP). Both the switch point and the CPP follow a latitudinal cline in European N. vitripennis populations. We previously showed that allelic frequencies of the clock gene period correlate with this diapause induction cline. Here we report that circadian expression of four clock genes-period (per), cryptochrome-2 (cry-2), clock (clk), and cycle (cyc)-oscillates as a function of photoperiod and latitude of origin in wasps from populations from the extremes of the cline. Expression amplitudes are lower in northern wasps, indicating a weaker, more plastic clock. Northern wasps also have a later onset of activity and longer free-running rhythms under constant conditions. RNA interference of per caused speeding up of the circadian clock, changed the expression of other clock genes, and delayed diapause in both southern and northern wasps. These results point toward adaptive latitudinal clock gene expression differences and to a key role of per in the timing of photoperiodic diapause induction of N. vitripennis.


Assuntos
Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Ritmo Circadiano , Diapausa de Inseto , Vespas/metabolismo , Animais , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Fotoperíodo , Interferência de RNA , Vespas/genética
14.
Tree Physiol ; 39(5): 861-876, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31034013

RESUMO

The MADS-box family genes play critical roles in the regulation of growth and development of flowering plants. AGAMOUS-LIKE 6 (AGL6)-like genes are one of the most enigmatic subfamilies of the MADS-box family because of highly variable expression patterns and ambiguous functions, which have long puzzled researchers. A lot of AGL6 homologs have been identified from gymnosperms and angiosperms. However, only a few have been characterized, especially for basal angiosperm taxa. Magnolia wufengensis is a woody basal angiosperm from the family Magnoliaceae. In the current study, the phylogenesis, expression and protein-protein interaction (PPI) patterns, and functions of two AGL6 homologs from M. wufengensis, MawuAGL6-1 and MawuAGL6-2, were analyzed. Phylogenetic analysis indicated that the two AGL6 duplicates may have arisen by gene duplication before the divergence of Magnoliaceae and Lauraceae, with the diversification of their expression and PPI patterns after gene duplication. Functional analysis revealed that, in addition to common functions in accelerating flowering, MawuAGL6-1 might be responsible for flower meristem determinacy, while MawuAGL6-2 is preferentially recruited to regulate tepal morphogenesis. These findings further advance our understanding of the evolution of phylogenesis, expression, interaction and functions of AGL6 lineage genes from basal angiosperms, as well as the entire AGL6 lineage genes, and the significance of AGL6 lineage genes in the evolution and biological diversity.


Assuntos
Duplicação Gênica , Expressão Gênica , Magnolia/genética , Proteínas Circadianas Period/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Evolução Molecular , Magnolia/metabolismo , Proteínas Circadianas Period/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
15.
Biol Res ; 52(1): 25, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31018872

RESUMO

BACKGROUND: The morphological diversity of flower organs is closely related to functional divergence within the MADS-box gene family. Bryophytes and seedless vascular plants have MADS-box genes but do not have ABCDE or AGAMOUS-LIKE6 (AGL6) genes. ABCDE and AGL6 genes belong to the subgroup of MADS-box genes. Previous works suggest that the B gene was the first ABCDE and AGL6 genes to emerge in plant but there are no mentions about the probable origin time of ACDE and AGL6 genes. Here, we collected ABCDE and AGL6 gene 381 protein sequences and 361 coding sequences from gymnosperms and angiosperms and reconstructed a complete Bayesian phylogeny of these genes. In this study, we want to clarify the probable origin time of ABCDE and AGL6 genes is a great help for understanding the role of the formation of the flower, which can decipher the forming order of MADS-box genes in the future. RESULTS: These genes appeared to have been under purifying selection and their evolutionary rates are not significantly different from each other. Using the Bayesian evolutionary analysis by sampling trees (BEAST) tool, we estimated that: the mutation rate of the ABCDE and AGL6 genes was 2.617 × 10-3 substitutions/site/million years, and that B genes originated 339 million years ago (MYA), CD genes originated 322 MYA, and A genes shared the most recent common ancestor with E/AGL6 296 MYA, respectively. CONCLUSIONS: The phylogeny of ABCDE and AGL6 genes subfamilies differed. The APETALA1 (AP1 or A gene) subfamily clustered into one group. The APETALA3/PISTILLATA (AP3/PI or B genes) subfamily clustered into two groups: the AP3 and PI clades. The AGAMOUS/SHATTERPROOF/SEEDSTICK (AG/SHP/STK or CD genes) subfamily clustered into a single group. The SEPALLATA (SEP or E gene) subfamily in angiosperms clustered into two groups: the SEP1/2/4 and SEP3 clades. The AGL6 subfamily clustered into a single group. Moreover, ABCDE and AGL6 genes appeared in the following order: AP3/PI → AG/SHP/STK → AGL6/SEP/AP1. In this study, we collected candidate sequences from gymnosperms and angiosperms. This study highlights important events in the evolutionary history of the ABCDE and AGL6 gene families and clarifies their evolutionary path.


Assuntos
Proteínas de Arabidopsis/genética , Cycadopsida/genética , Proteínas de Domínio MADS/genética , Magnoliopsida/genética , Proteínas Circadianas Period/genética , Filogenia , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta
16.
Cells ; 8(4)2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30979023

RESUMO

The floral perianth, comprising sepals and petals, conceals the sexual organs and attracts pollinators. The coordination of growth and scent emission is not fully understood. We have analyzed the effect of knocking down CHANEL (PhCHL), the ZEITLUPE ortholog in petunia (PhCHL) by hairpin RNAs. Plants with low PhCHL mRNA had overall decreased size. Growth evaluation using time lapse image analysis showed that early leaf movement was not affected by RNAi:PhCHL, but flower angle movement was modified, moving earlier during the day in knockdown plants than in wild types. Despite differences in stem length, growth rate was not significantly affected by loss of PhCHL. In contrast, petal growth displayed lower growth rate in RNAi:PhCHL. Decreased levels of PhCHL caused strongly modified scent profiles, including changes in composition and timing of emission resulting in volatile profiles highly divergent from the wild type. Our results show a role of PhCHL in controlling growth and development of vegetative and reproductive organs in petunia. The different effects of PhCHL on organ development indicate an organ-specific interpretation of the down regulation of PhCHL. Through the control of both timing and quantitative volatile emissions, PhCHL appears to be a major coordinator of scent profiles.


Assuntos
Flores/crescimento & desenvolvimento , Odorantes/análise , Proteínas Circadianas Period , Petunia , Regulação da Expressão Gênica de Plantas , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/fisiologia , Petunia/genética , Petunia/crescimento & desenvolvimento
17.
Hum Cell ; 32(3): 275-284, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30941700

RESUMO

This study aimed to characterize the pathophysiology, including possible correlations, of clock gene expression and erythropoietin (EPO) production in the acute stage of blood hemorrhage. Specimens of human cortical tissues (right and left kidneys) and cardiac blood were collected at autopsy from 52 cases following mortality due to acute-stage blood hemorrhage following sharp instrument injury. BMAL1 and PER2 mRNA levels were determined by reverse transcription-polymerase chain reaction; BMAL1 and PER2 protein levels were assessed using immunohistochemistry; BMAL1 protein levels were quantitatively measured by western blotting; and serum EPO levels were measured by chemiluminescent enzyme immunoassay. Separately, a rat model of hemorrhagic conditions was generated and used to confirm the results obtained with autopsy-derived specimens. A positive correlation was observed between BMAL1 protein and serum EPO levels, but not between BMAL1 mRNA levels and serum EPO levels. We also noted that Per2 mRNA expression became elevated in humans who survived for > 3 h after acute hemorrhagic events, with subsequent decreases in serum EPO levels. The rat model showed that even short (30-min) intervals of blood loss yielded increases in both Bmal1 mRNA and serum EPO levels; longer (60-min) intervals resulted in increases in Per2 mRNA expression along with decreases in serum EPO. Thus, the acute-stage human hemorrhage cases and the rat hemorrhage model yielded similar tendencies for clock gene expression and EPO secretion. In conclusion, our results indicated that clock genes are involved in the regulation of EPO production during the early stages of hypoxia/ischemia resulting from the acute hemorrhagic events.


Assuntos
Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Eritropoetina/metabolismo , Expressão Gênica , Hemorragia/genética , Hemorragia/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Choque Hemorrágico/genética , Choque Hemorrágico/metabolismo , Doença Aguda , Animais , Modelos Animais de Doenças , Humanos , Masculino , Mudanças Depois da Morte , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Fatores de Tempo
18.
Int J Nanomedicine ; 14: 1299-1309, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30863062

RESUMO

Aim: Paclitaxel (PTX) is an effective antitumor drug. Previous research demonstrated that paclitaxel nanoparticles (PTX-NPs) exhibited the greatest antitumor effect at 15 hours after light onset (15 HALO), but the mechanism in chronic chemotherapy is still unknown. In our study, we investigated whether PTX-NPs regulated Period2 (Per2) during chronic chemotherapy to induce apoptosis in vivo and in vitro. Methods: To improve the antitumor effect and reduce organ damage induced by PTX treatment, PTX-NPs were prepared using a film dispersion method. Then, A549 cells were treated with PTX-NPs at 0, 5, 10, 15, and 20 HALO. An annexin/PI V-FITC apoptosis kit was measured for apoptosis, and PI was analyzed for cell cycle. The relative mechanism was detected by RT-PCR and Western blotting. Tumor volume and weight were measured to evaluate the antitumor effect of the PTX-NPs, and H&E staining was performed to assess organ damage. Results: Cell cycle analysis demonstrated that PTX-NPs blocked cell cycle in G2 phase and that the ratio of cell death was significantly increased in A549 cells, while the ratios of cells in G2 phase and of apoptotic cells were highest at 15 HALO. Evaluation of in vivo antitumor activity revealed that PTX-NPs inhibited tumor growth and decreased tumor weight at 15 HALO. RT-PCR and Western blotting demonstrated that PTX-NPs upregulated Per2 mRNA and protein expression, and the highest Per2 expression was observed at 15 HALO in vivo and in vitro. Meanwhile, Bax mRNA and protein expression was upregulated, while Bcl-2 mRNA and protein expression was downregulated after PTX-NPs treatment in vivo. Moreover, H&E staining revealed that PTX-NPs reduced liver damage at 15 HALO. Conclusion: PTX-NPs exhibited the most effective antitumor activity and reduced liver damage at 15 HALO through upregulation of Per2 expression to induce apoptosis in vivo and in vitro.


Assuntos
Apoptose/efeitos dos fármacos , Nanopartículas/química , Paclitaxel/uso terapêutico , Células A549 , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Nanopartículas/ultraestrutura , Paclitaxel/farmacologia , Tamanho da Partícula , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
19.
Biochem Biophys Res Commun ; 512(2): 344-351, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30894276

RESUMO

Ultraviolet-C (UVC) electromagnetic radiation is the most damaging type of the UV radiation and causes many cellular and physiological responses. UVC has been using for sterilization and disinfection, and the risk of exposure to the UVC is increasing. Here, we determined the effect of the UVC on the cellular circadian clock system. UVC irradiation synchronized the biological clock system and induced time-dependent expression of clock genes including Clock, Cry1, and Per1. The rhythmic expression of clock genes is also followed by time-dependent mRNA degradation or non-canonical translation initiation of clock genes. Furthermore, we show a translocation of PERIOD1 (PER1) protein after UVC irradiation, which mediates the rhythmic feedback loop of clock genes. Our results suggest that UVC can synchronize the circadian clock system, and induces rhythmic expression of clock genes via time-dependent transcription, post-transcription, and post-translational modification.


Assuntos
Ritmo Circadiano/efeitos da radiação , Raios Ultravioleta , Transporte Ativo do Núcleo Celular/efeitos da radiação , Animais , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , Criptocromos/genética , Criptocromos/metabolismo , Fibroblastos/fisiologia , Fibroblastos/efeitos da radiação , Camundongos , Células NIH 3T3 , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Biossíntese de Proteínas/efeitos da radiação , Estabilidade de RNA/efeitos da radiação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
20.
Ann Anat ; 223: 43-48, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30716467

RESUMO

BACKGROUND: Ultrasonic vocalizations (USV) of mice are produced in and emitted by the larynx. However, which anatomical elements of the mouse larynx are involved and to which aspects of USV they contribute is not clear. Frequency and amplitude parameters of mice, deficient in the clock gene Period1 (mPer1-/- mice) are distinguishably different compared to C3H wildtype (WT) controls. Because structural differences in the larynx may be a reason for the different USV observed, we analyzed laryngeal anatomy of mPer1-/- mice and WT control animals using micro-computed-tomography and stereology. RESULTS: In mPer1-/- mice, we found laryngeal cartilages to be normally arranged, and the thyroid, arytenoid and epiglottal cartilages were similar in diameter and volume measurements, compared to WT mice. However, in the cricoid cartilage, a significant difference in the dorso-ventral diameter and volume was evident. CONCLUSION: Our findings imply that laryngeal morphology is affected by inactivation of the clock gene Period1 in mice, which may contribute to their abnormal USV.


Assuntos
Laringe/anatomia & histologia , Camundongos Endogâmicos C3H/anatomia & histologia , Proteínas Circadianas Period/deficiência , Vocalização Animal/fisiologia , Animais , Imagem Tridimensional , Laringe/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos C3H/genética , Camundongos Endogâmicos C3H/fisiologia , Proteínas Circadianas Period/genética , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
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