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1.
J Insect Physiol ; 155: 104636, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38609008

RESUMO

Photic entrainment is an essential function of the circadian clock, which enables organisms to set the appropriate timing of daily behavioral and physiological events. Recent studies have shown that the mechanisms of the circadian clock and photic entrainment vary among insect species. This study aimed to elucidate the circadian photoreceptors necessary for photic entrainment in firebrats Thermobia domestica, one of the most primitive apterygote insects. A homology search of publicly available RNA sequence (RNA-seq) data from T. domestica exhibited a cryptochrome 2 (cry2) gene and three opsin genes, opsin long wavelength 1 (opLW1), opLW2, and opUV, as candidate circadian photoreceptors. We examined the possible involvement of these genes in photic entrainment of firebrat locomotor rhythms. Firebrats had the highest entrainability to the light-dark cycle of green light. Treatment with dsRNA of the candidate genes strongly downregulated the respective targeted genes, and in the case of opsin genes, other untargeted genes were occasionally downregulated to various degrees. Under constant light, most control firebrats became arrhythmic, whereas a fraction of those treated with double RNAi of the two opLWs remained rhythmic. Behavioral experiments revealed that the transient cycles necessary for re-entrainment to shifted light cycles were lengthened when opLW2 expression was reduced. These results suggest that opLW2 is involved in the photic entrainment of circadian rhythm in firebrats.

2.
J Occup Health ; 65(1): e12397, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37017650

RESUMO

OBJECTIVES: This study examined the effectiveness of a newly developed work-family life support program on the work-family interface and mental health indicators among Japanese dual-earner couples with a preschool child(/ren) using a randomized controlled trial with a waitlist. METHODS: Participants who met the inclusion criteria were randomly allocated to the intervention or the control groups (n = 79 and n = 85, respectively). The program comprised two 3-h sessions with a 1-month interval between them and provided comprehensive skills by including self-management, couple management, and parenting management components. The program sessions were conducted on weekends in a community center room with 3-10 participants. Outcomes were assessed at baseline, 1-month, and 3-month follow-ups. Primary outcomes were work-family balance self-efficacy (WFBSE), four types of work-family spillovers (i.e., work-to-family conflict, family-to-work conflict, work-to-family facilitation, and family-to-work facilitation), psychological distress, and work engagement reported by the participants. RESULTS: The program had significantly pooled intervention effects on WFBSE (P = .031) and psychological distress (P = .014). The effect sizes (Cohen's d) were small, with values of 0.22 at the 1-month follow-up and 0.24 at the 3-month follow-up for WFBSE, and -0.36 at the 3-month follow-up for psychological distress. However, the program had nonsignificant pooled effects on four types of work-family spillovers and work engagement. CONCLUSIONS: The program effectively increased WFBSE and decreased psychological distress among Japanese dual-earner couples with a preschool child(/ren).


Assuntos
Saúde Mental , Angústia Psicológica , Equilíbrio Trabalho-Vida , Humanos , População do Leste Asiático , Apoio Familiar , Pais , Emprego
3.
Zoolog Sci ; 40(1): 53-63, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36744710

RESUMO

Photic entrainment is an essential property of the circadian clock that sets the appropriate timing of daily behavioral and physiological events. However, the molecular mechanisms underlying the entrainment remain largely unknown. In the cricket Gryllus bimaculatus, the immediate early gene c-fosB plays an important role in photic entrainment, followed by a mechanism involving cryptochromes (crys). However, the association between c-fosB expression and crys remains unclear. In the present study, using RNA-sequencing analysis, we found that five Fbxl family genes (Fbxl4, Fbxl5, Fbxl16, Fbxl-like1, and Fbxl-like2) encoding F-box and leucine-rich repeat proteins are likely involved in the mechanism following light-dependent c-fosB induction. RNA interference (RNAi) of c-fosA/B significantly downregulated Fbxls expression, whereas RNAi of the Fbxl genes exerted no effect on c-fosB expression. The Fbxl genes showed rhythmic expression under light-dark cycles (LDs) with higher expression levels in early day (Fbxl16), whole day (Fbxl-like1), or day-to-early night (Fbxl4, Fbxl5, and Fbxl-like2), whereas their expression was reduced in the dark. We then examined the effect of their RNAi on the photic entrainment of the locomotor rhythm and found that RNAi of Fbxl4 either disrupted or significantly delayed the re-entrainment of the locomotor rhythm to shifted LDs. These results suggest that light-induced c-fosB expression stimulates Fbxl4 expression to reset the circadian clock.


Assuntos
Relógios Circadianos , Gryllidae , Animais , Gryllidae/fisiologia , Ritmo Circadiano/fisiologia , Relógios Circadianos/genética , Fotoperíodo , Interferência de RNA , Estimulação Luminosa/métodos , Luz
4.
J Phys Chem B ; 126(49): 10490-10499, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36417887

RESUMO

We analyzed the primary properties of ionic liquids (ILs) comprising quaternary phosphonium cations and bis(trifluoromethylsulfonyl) amide anions and compared them with those of corresponding quaternary-ammonium-cation-based ILs. Broadband dielectric spectroscopy was used to confirm the coupling between the translational and orientational motions of ions, and our results demonstrated that the high ionic conductivity of the phosphonium-based ILs was attributed to their fast rotational dynamics. The differences between ILs with different cations were further evaluated using vibrational (Raman and terahertz) spectroscopy. The Raman spectroscopy data revealed that the cation structure affected the conformation and flexibility (conformational change) of the anion. Furthermore, terahertz spectroscopy allowed us to evaluate the relationship between ion transport and intermolecular interactions between the cation and anion of ILs.


Assuntos
Compostos de Amônio , Líquidos Iônicos , Líquidos Iônicos/química , Compostos de Amônio/química , Cátions/química , Ânions/química , Análise Espectral
5.
Zoolog Sci ; 39(5): 459-467, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36205367

RESUMO

Most insects show circadian rhythms of which the free-running period changes in a light-dependent manner and is generally longer under constant light (LL) than under constant dark conditions in nocturnal animals. However, the mechanism underlying this LL-dependent period change remains unclear. Here, using the cricket Gryllus bimaculatus, we examined the effects of long-term LL exposure on the free-running period of locomotor rhythms. Initially, the free-running period was considerably longer than 24 h but it gradually became shorter during long-term exposure to LL. The initial lengthening and ensuing gradual shortening under long-term LL exposure were observed even after unilateral removal of the optic lobe. Thus, these changes in the free-running period could be attributable to a single optic lobe clock. RNA interference (RNAi)-mediated silencing of the clock genes Par domain protein 1 (Pdp1) and timeless (tim) revealed that the treatments eliminated the initial period lengthening by LL without reducing circadian photoreceptor gene expression. However, they did not affect the period shortening during long-term LL exposure. The slopes of the regression line for the period change during long-term LL for Pdp1RNAi-treated and timRNAi-treated crickets were not different from that of the dsDsRed2-treated control. These results suggest that the initial period lengthening after transfer to LL requires tim and Pdp1, while the ensuing period shortening during long-term LL exposure is caused by a mechanism independent of tim and Pdp1.


Assuntos
Gryllidae , Animais , Ritmo Circadiano , Gryllidae/genética , Gryllidae/metabolismo , Luz , Interferência de RNA
6.
Zoolog Sci ; 39(4)2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35960036

RESUMO

The light cycle is the most powerful Zeitgeber entraining the circadian clock in most organisms. Insects use CRYPTOCHROMEs (CRYs) and/or the compound eye for the light perception necessary for photic entrainment. The molecular mechanism underlying CRY-dependent entrainment is well understood, while that of the compound eye-dependent entrainment remains to be elucidated. Using molecular and behavioral experiments, we investigated the role of timeless (tim) in the photic entrainment mechanism in the cricket Gryllus bimaculatus. RNA interference of tim (timRNAi) disrupted the entrainment or prolonged the transients for resynchronization to phase-delayed light-dark cycles. The treatment reduced the magnitude of phase delay caused by delayed light-off, but augmented advance shifts caused by light exposure at late night. TIM protein levels showed daily cycling with an increase during the night and reduction by light exposure at both early and late night. These results suggest that tim plays a critical role in the entrainment to delayed light cycles.


Assuntos
Relógios Circadianos , Gryllidae , Animais , Relógios Circadianos/genética , Ritmo Circadiano , Gryllidae/genética , Luz , Fotoperíodo , Interferência de RNA
7.
Angew Chem Int Ed Engl ; 55(1): 278-82, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26509649

RESUMO

Intermolecular [2+2+1] carbonylative cycloaddition of aldehydes with alkynes and subsequent oxidation to γ-hydroxybutenolides is achieved using a supported ruthenium catalyst. A ceria-supported ruthenium catalyst promotes the reaction efficiently, even with an ambient pressure of CO or without external CO, thus giving the corresponding γ-hydroxybutenolide derivatives in good to high yields. Moreover this catalyst can be reused with no loss of activity.

8.
J Synchrotron Radiat ; 20(Pt 6): 869-74, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24121330

RESUMO

Lipid liposomes are promising drug delivery systems because they have superior curative effects owing to their high adaptability to a living body. Lipid liposomes encapsulating proteins were constructed and the structures examined using synchrotron radiation small- and wide-angle X-ray scattering (SR-SWAXS). The liposomes were prepared by a sequential combination of natural swelling, ultrasonic dispersion, freeze-throw, extrusion and spin-filtration. The liposomes were composed of acidic glycosphingolipid (ganglioside), cholesterol and phospholipids. By using shell-modeling methods, the asymmetric bilayer structure of the liposome and the encapsulation efficiency of proteins were determined. As well as other analytical techniques, SR-SWAXS and shell-modeling methods are shown to be a powerful tool for characterizing in situ structures of lipid liposomes as an important candidate of drug delivery systems.


Assuntos
Lipossomos , Modelos Químicos , Proteínas/química , Espalhamento de Radiação , Raios X
9.
Appl Environ Microbiol ; 79(23): 7241-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24038698

RESUMO

Bacterial chemotaxis influences the ability of bacteria to survive and thrive in most environments, including polluted ones. Despite numerous reports of the phenotypic characterization of chemotactic bacteria, only a few molecular details of chemoreceptors for aromatic pollutants have been described. In this study, the molecular basis of chemotaxis toward an environmentally toxic chlorinated aromatic pollutant, 4-chloroaniline (4CA), was evaluated. Among the three Pseudomonas spp. tested, Pseudomonas aeruginosa PAO1 exhibited positive chemotaxis both to the nonmetabolizable 4CA, where 4-chloroacetanilide was formed as a dead-end transformation product, and to the metabolizable catechol. Molecular analysis of all 26 mutants with a disrupted methyl-accepting chemotaxis gene revealed that CtpL, a chromosomally encoded chemoreceptor, was responsible for the positive chemotactic response toward 4CA. Since CtpL has previously been described to be a major chemoreceptor for inorganic phosphate at low concentrations in PAO1, this report describes a fortuitous ability of CtpL to function toward aromatic pollutants. In addition, its regulation not only was dependent on the presence of the chemoattractant inducer but also was regulated by conditions of phosphate starvation. These results expand the range of known chemotactic transducers and their function in the environmental bacterium PAO1.


Assuntos
Compostos de Anilina/metabolismo , Catecóis/metabolismo , Quimiotaxia , Poluentes Ambientais/metabolismo , Pseudomonas aeruginosa/fisiologia , Receptores de Superfície Celular/metabolismo , Mutação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Receptores de Superfície Celular/genética
10.
Eur Phys J E Soft Matter ; 36(7): 74, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23852578

RESUMO

While the steady-state existence in the size and shape of liquid-ordered microdomains in cell membranes, the so-called "lipid rafts", still remain the subject of debate, glycosphingolipid-cholesterol rich regions in plasma membranes have been considered to have a function as platforms for signaling and sorting. In addition, recent spectroscopic studies show that the interaction between monosialoganglioside and amyloid beta (Aß protein promotes the transition of Aß from the native structure to the cross-beta fold in amyloid aggregates. However, there is few evidence on the dynamics of "lipid rafts" membranes. As the neutron spin-echo (NSE) technique is well known to detect directly slow dynamics of membrane systems in situ, by the combination of NSE and small-angle X-ray scattering we have studied the effect of the interaction between raft-model membrane and amyloid Aß proteins on the structure and dynamics of a large uni-lamellar vesicle (LUV) consisting of monosialoganglioside-cholesterol-phospholipid ternary mixtures as a model of lipid-raft membrane. We have found that the interaction between the Aß proteins and the model membrane at the liquid crystal phase significantly suppresses a bending-diffusion motion with a minor effect on the LUV structure. The present results would suggest a possibility of non-receptor-mediated disorder in signaling through a modulation of a membrane dynamics induced by the association of amyloidogenic peptides on a plasma membrane.


Assuntos
Peptídeos beta-Amiloides/química , Microdomínios da Membrana/química , Peptídeos beta-Amiloides/metabolismo , Colesterol/química , Gangliosídeo G(M1)/química , Microdomínios da Membrana/metabolismo , Ligação Proteica , Espalhamento a Baixo Ângulo , Lipossomas Unilamelares/química , Difração de Raios X
11.
J Biol Chem ; 286(29): 25770-7, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21592968

RESUMO

To identify molecules that play roles in the clearance of apoptotic cells by Drosophila phagocytes, we examined a series of monoclonal antibodies raised against larval hemocytes for effects on phagocytosis in vitro. One antibody that inhibited phagocytosis recognized terribly reduced optic lobes (Trol), a core protein of the perlecan-type proteoglycan, and the level of phagocytosis in embryos of a Trol-lacking fly line was lower than in a control line. The treatment of a hemocyte cell line with a recombinant Trol protein containing the amino acid sequence RGD augmented the phosphorylation of focal adhesion kinase, a hallmark of integrin activation. A loss of integrin ßν, one of the two ß subunits of Drosophila integrin, brought about a reduction in the level of apoptotic cell clearance in embryos. The presence of integrin ßν at the surface of embryonic hemocytes was confirmed, and forced expression of integrin ßν in hemocytes of an integrin ßν-lacking fly line recovered the defective phenotype of phagocytosis. Finally, the level of phagocytosis in a fly line that lacks both integrin ßν and Draper, another receptor required for the phagocytosis of apoptotic cells, was lower than that in a fly line lacking either protein. We suggest that integrin ßν serves as a phagocytosis receptor responsible for the clearance of apoptotic cells in Drosophila, independent of Draper.


Assuntos
Apoptose , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Embrião não Mamífero/citologia , Cadeias beta de Integrinas/metabolismo , Fagocitose , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Proteínas de Drosophila/imunologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero/metabolismo , Hemócitos/citologia , Hemócitos/metabolismo , Humanos , Cadeias beta de Integrinas/imunologia , Larva/citologia , Larva/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Lobo Óptico de Animais não Mamíferos/citologia , Lobo Óptico de Animais não Mamíferos/metabolismo , Fagócitos/citologia , Fagócitos/metabolismo
12.
Evolution ; 57(10): 2365-73, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14628924

RESUMO

In a colony headed by a single monandrous foundress, theories predict that conflicts between a queen and her workers over both sex ratio and male production should be intense. If production of males by workers is a function of colony size, this should affect sex ratios, but few studies have examined how queens and workers resolve both conflicts simultaneously. We conducted field and laboratory studies to test whether sex-ratio variation can be explained by conflict over male production between queen and workers in the primitively eusocial wasp Polistes chinensis antennalis. Worker oviposition rate increased more rapidly with colony size than did queen oviposition. Allozyme and microsatellite markers revealed that the mean frequency of workers' sons among male adults in queen-right colonies was 0.39 +/- 0.08 SE (n = 22). Genetic relatedness among female nestmates was high (0.654-0.796), showing that colonies usually had a single, monandrous queen. The mean sex allocation ratio (male investment/male and gyne investments) of 46 queen-right colonies was 0.47 +/- 0.02, and for 25 orphaned colonies was 0.86 +/- 0.04. The observed sex allocation ratio was likely to be under queen control. For queen-right colonies, the larger colonies invested more in males and produced reproductives protandrously and/or simultaneously, whereas the smaller colonies invested more in females and produced reproductives protogynously. Instead of positive relationships between colony size and worker oviposition rate, the frequency of workers' sons within queen-right colonies did not increase with colony size. These results suggest that queens control colony investment, even though they allow worker oviposition in queen-right colonies. Eggs laid by workers may be policed by the queen and/or fellow workers. Worker oviposition did not influence the outcome of sex allocation ratio as a straightforward function of colony size.


Assuntos
Comportamento Alimentar , Modelos Biológicos , Razão de Masculinidade , Comportamento Sexual Animal/fisiologia , Vespas/fisiologia , Alelos , Animais , Evolução Biológica , Eletroforese , Feminino , Masculino , Repetições de Microssatélites , Densidade Demográfica , Reprodução/fisiologia
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