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1.
Eur J Med Chem ; 271: 116417, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38688063

RESUMO

Since synovial hypoxic microenvironment significantly promotes the pathological progress of rheumatoid arthritis (RA), hypoxia-inducible factor 1 (HIF-1) has been emerged as a promising target for the development of novel therapeutic agents for RA treatment. In this study, we designed and synthesized a series of diaryl substituted isoquinolin-1(2H)-one derivatives as HIF-1 signaling inhibitors using scaffold-hopping strategy. By modifying the substituents on N-atom and 6-position of isoquinolin-1-one, we discovered compound 17q with the most potent activities against HIF-1 (IC50 = 0.55 µM) in a hypoxia-reactive element (HRE) luciferase reporter assay. Further pharmacological studies revealed that 17q concentration-dependently blocked hypoxia-induced HIF-1α protein accumulation, reduced inflammation response, inhibited cellular invasiveness and promoted VHL-dependent HIF-1α degradation in human RA synovial cell line. Moreover, 17q improved the pathological injury of ankle joints, decreased angiogenesis and attenuated inflammation response in the adjuvant-induced arthritis (AIA) rat model, indicating the promising therapeutic potential of compound 17q as an effective HIF-1 inhibitor for RA therapy.


Assuntos
Artrite Reumatoide , Isoquinolinas , Transdução de Sinais , Animais , Humanos , Masculino , Ratos , Antirreumáticos/farmacologia , Antirreumáticos/química , Antirreumáticos/síntese química , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Artrite Experimental/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Relação Dose-Resposta a Droga , Descoberta de Drogas , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/química , Isoquinolinas/farmacologia , Isoquinolinas/síntese química , Estrutura Molecular , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Quinolonas/síntese química , Quinolonas/química , Quinolonas/farmacologia
2.
Cell Rep ; 43(2): 113708, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38294902

RESUMO

Organisms sensing environmental cues and internal states and integrating the sensory information to control fecundity are essential for survival and proliferation. The present study finds that a moderate cold temperature of 11°C reduces egg laying in Caenorhabditis elegans. ASEL and AWC neurons sense the cold via GCY-20 signaling and act antagonistically on egg laying through the ASEL and AWC/AIA/HSN circuits. Upon cold stimulation, ASEL and AWC release glutamate to activate and inhibit AIA interneurons by acting on highly and lowly sensitive ionotropic GLR-2 and GLC-3 receptors, respectively. AIA inhibits HSN motor neuron activity via acetylcholinergic ACR-14 receptor signaling and suppresses egg laying. Thus, ASEL and AWC initiate and reduce the cold suppression of egg laying. ASEL's action on AIA and egg laying dominates AWC's action. The biased opposite actions of these neurons on egg laying provide animals with a precise adaptation of reproductive behavior to environmental temperatures.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Temperatura Baixa , Transdução de Sinais/fisiologia , Neurônios Motores/fisiologia
3.
Front Mol Neurosci ; 16: 1101628, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008778

RESUMO

Sensations, especially nociception, are tightly controlled and regulated by the central and peripheral nervous systems. Osmotic sensation and related physiological and behavioral reactions are essential for animal well-being and survival. In this study, we find that interaction between secondary nociceptive ADL and primary nociceptive ASH neurons upregulates Caenorhabditis elegans avoidance of the mild and medium hyperosmolality of 0.41 and 0.88 Osm but does not affect avoidance of high osmolality of 1.37 and 2.29 Osm. The interaction between ASH and ADL is actualized through a negative feedback circuit consisting of ASH, ADL, and RIM interneurons. In this circuit, hyperosmolality-sensitive ADL augments the ASH hyperosmotic response and animal hyperosmotic avoidance; RIM inhibits ADL and is excited by ASH; thus, ASH exciting RIM reduces ADL augmenting ASH. The neuronal signal integration modality in the circuit is disexcitation. In addition, ASH promotes hyperosmotic avoidance through ASH/RIC/AIY feedforward circuit. Finally, we find that in addition to ASH and ADL, multiple sensory neurons are involved in hyperosmotic sensation and avoidance behavior.

4.
iScience ; 25(11): 105287, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36304123

RESUMO

Central and peripheral sensory neurons tightly regulate nociception and avoidance behavior. The peripheral modulation of nociception provides more veridical and instantaneous information for animals to achieve rapid, more fine-tuned and concentrated behavioral responses. In this study, we find that positive interaction between ASH and ASK sensory neurons is essential for the fast-rising phase of ASH Ca2+ responses to noxious copper ions and inhibits the adaption of avoiding Cu2+. We reveal the underlying neuronal circuit mechanism. ASK accelerates the ASH Ca2+ responses by transferring cGMP through gap junctions. ASH excites ASK via a disinhibitory neuronal circuit composed of ASH, AIA, and ASK. Avoidance adaptation depends on the slope rate of the rising phase of ASH Ca2+ responses. Thus, in addition to amplitude, sensory kinetics is significant for sensations and behaviors, especially for sensory and behavioral adaptations.

5.
Microb Drug Resist ; 28(4): 461-467, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35148485

RESUMO

Objective: To evaluate the effectiveness of Xpert MTB/RIF in patients with multidrug-resistant tuberculosis (MDR-TB). Methods: Seventy-five patients with MDR-TB were enrolled in this prospective cohort study and were divided into two groups. The observation group were given standardized anti-MDR-TB treatment regimen (6ZAmLfxPtoCs/18ZLfxPtoCs) immediately when they had two positive sputum Xpert MTB/RIF results of RIF resistance. The control group were not given standardized anti-MDR-TB regimen until culture-based drug-susceptibility testing suggested MDR-TB. Treatment effect index, foci absorption, conversion of sputum, treatment outcomes, and adverse reactions were observed. Fisher's exact test and chi-square test were used to compare the differences between groups. Results: Treatment effect index of the observation group significantly out-performed the control group (24/34, 70.6% vs. 17/38, 44.7%, p = 0.027). At the 6th month of treatment course, observation group achieved significantly higher conversion (28/34, 82.3% vs. 23/38, 60.5%, p = 0.042). The foci absorption, cavity change, conversion at the 24th month of course, or treatment outcome between two groups were not statistically different. Conclusion: Xpert MTB/RIF helps MDR-TB patients to start rational treatment regimen earlier and reach earlier sputum conversion.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antibacterianos/farmacologia , Humanos , Mycobacterium tuberculosis/genética , Estudos Prospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , Sensibilidade e Especificidade , Escarro , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
6.
Cell Rep ; 38(6): 110330, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35139370

RESUMO

Escape is an evolutionarily conserved and essential avoidance response. Considered to be innate, most studies on escape responses focused on hard-wired circuits. We report here that a neuropeptide NLP-18 and its cholecystokinin receptor CKR-1 enable the escape circuit to execute a full omega (Ω) turn. We demonstrate in vivo NLP-18 is mainly secreted by the gustatory sensory neuron (ASI) to activate CKR-1 in the head motor neuron (SMD) and the turn-initiating interneuron (AIB). Removal of NLP-18 or CKR-1 or specific knockdown of CKR-1 in SMD or AIB neurons leads to shallower turns, hence less robust escape steering. Consistently, elevation of head motor neuron (SMD)'s Ca2+ transients during escape steering is attenuated upon the removal of NLP-18 or CKR-1. In vitro, synthetic NLP-18 directly evokes CKR-1-dependent currents in oocytes and CKR-1-dependent Ca2+ transients in SMD. Thus, cholecystokinin peptidergic signaling modulates an escape circuit to generate robust escape steering.


Assuntos
Colecistocinina/metabolismo , Neuropeptídeos/metabolismo , Células Receptoras Sensoriais/fisiologia , Transdução de Sinais/fisiologia , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans , Locomoção/fisiologia
7.
FASEB J ; 35(1): e21202, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33368638

RESUMO

Among the fascinating adaptations to limiting oxygen conditions (hypoxia) is the suppression of food intake and weight loss. In humans, this phenomenon is called high-altitude anorexia and is observed in people suffering from acute mountain syndrome. The high-altitude anorexia appears to be conserved in evolution and has been seen in species across the animal kingdom. However, the mechanism underlying the recovery of eating behavior after hypoxia is still not known. Here, we show that the phosphatidylinositol transfer protein PITP-1 is essential for the fast recovery of eating behavior after hypoxia in the nematode Caenorhabditis elegans. Unlike the neuroglobin GLB-5 that accelerates the recovery of eating behavior through its function in the oxygen (O2 )-sensing neurons, PITP-1 appears to act downstream, in neurons that express the mod-1 serotonin receptor. Indeed, pitp-1 mutants display wild-type-like O2 -evoked-calcium responses in the URX O2 -sensing neuron. Intriguingly, loss-of-function of protein kinase C 1 (PKC-1) rescues pitp-1 mutants' recovery after hypoxia. Increased diacylglycerol (DAG), which activates PKC-1, attenuates the recovery of wild-type worms. Together, these data suggest that PITP-1 enables rapid recovery of eating behavior after hypoxia by limiting DAG's availability, thereby limiting PKC activity in mod-1-expressing neurons.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Hipóxia/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Hipóxia/genética , Proteínas de Transferência de Fosfolipídeos/genética
8.
J Natl Med Assoc ; 113(2): 212-217, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33268103

RESUMO

OBJECTIVE: To investigate and evaluate the clinical features of patients infected with the 2019 novel coronavirus (COVID-19) outside of Wuhan. METHODS: 105 patients admitted to our hospital with clinical- and laboratory-confirmed COVID-19 infection were studied. Data were collected from January 17, 2020 to March 5, 2020. RESULTS: 105 patients (57 male and 48 female) were confirmed to have COVID-19 infection. Among the 105 patients, 55 (52%) had made short trips to Wuhan during the two weeks before the onset of illness, and these were the first-generation confirmed cases. An exact date of close contact with someone in Wenzhou with confirmed or suspected COVID-19 infection from Wuhan (the second-generation confirmed cases) could be provided by 38 (36%) patients. Of the remaining patients, six (6%; the third-generation confirmed cases) were familial clusters of the second-generation confirmed cases, three (3%) had no definite epidemiological features, and 16 (15%) were from the same location as for the case report. CONCLUSION: Due to the infectiousness of COVID-19, patients with infections should be diagnosed and treated as early as possible after developing fever symptoms or showing other clinical characteristics or imaging features. With respect to high-risk cases, we must focus on any complications that arise and take effective measures to treat them immediately. This will significantly improve the prognosis of patients with severe infections.


Assuntos
Antivirais/administração & dosagem , COVID-19 , Hospitalização/estatística & dados numéricos , Metilprednisolona/administração & dosagem , Avaliação de Sintomas , Adulto , Anti-Inflamatórios/administração & dosagem , COVID-19/epidemiologia , COVID-19/fisiopatologia , COVID-19/terapia , Teste de Ácido Nucleico para COVID-19/métodos , Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , China/epidemiologia , Busca de Comunicante/métodos , Busca de Comunicante/estatística & dados numéricos , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , SARS-CoV-2/isolamento & purificação , Índice de Gravidade de Doença , Avaliação de Sintomas/métodos , Avaliação de Sintomas/estatística & dados numéricos , Tempo para o Tratamento , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
9.
iScience ; 23(10): 101588, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33089099

RESUMO

Animals' ability to sense environmental cues and to integrate this information to control fecundity is vital for continuing the species lineage. In this study, we observed that the sensory neurons Amphid neuron (ASHs and ADLs) differentially regulate egg-laying behavior in Caenorhabditis elegans under varied environmental conditions via distinct neuronal circuits. Under standard culture conditions, ASHs tonically release a small amount of glutamate and inhibit Hermaphrodite specific motor neuron (HSN) activities and egg laying via a highly sensitive Glutamate receptor (GLR)-5 receptor. In contrast, under Cu2+ stimulation, ASHs and ADLs may release a large amount of glutamate and inhibit Amphid interneuron (AIA) interneurons via low-sensitivity Glutamate-gated chloride channel (GLC)-3 receptor, thus removing the inhibitory roles of AIAs on HSN activity and egg laying. However, directly measuring the amount of glutamate released by sensory neurons under different conditions and assaying the binding kinetics of receptors with the neurotransmitter are still required to support this study directly.

10.
iScience ; 23(10): 101567, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33083734

RESUMO

Specific recording, labeling, and spatiotemporal manipulating neurons are essential for neuroscience research. In this study, we developed a tripartite spatiotemporal gene induction system in C. elegans, which is based on the knockout of two transcriptional terminators (stops in short) by two different recombinases FLP and CRE. The recombinase sites (loxP and FRT) flanked stops after a ubiquitous promoter terminate transcription of target genes. FLP and CRE, induced by two promoters of overlapping expression, remove the stops (subsequent FLP/CRE-out). The system provides an "AND" gate strategy for specific gene expression in single types of cell(s). Combined with an inducible promoter or element, the system can control the spatiotemporal expression of genes in defined cell types, especially in cells or tissues lacking a specific promoter. This tripartite FLP/CRE-out gene expression system is a simple, labor- and cost-saving toolbox for cell type-specific and inducible gene expression in C. elegans.

11.
Proc Natl Acad Sci U S A ; 116(14): 7107-7112, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30872487

RESUMO

Feeding is vital for animal survival and is tightly regulated by the endocrine and nervous systems. To study the mechanisms of humoral regulation of feeding behavior, we investigated serotonin (5-HT) and octopamine (OA) signaling in Caenorhabditis elegans, which uses pharyngeal pumping to ingest bacteria into the gut. We reveal that a cross-modulation mechanism between 5-HT and OA, which convey feeding and fasting signals, respectively, mainly functions in regulating the pumping and secretion of both neuromodulators via ADF/RIC/SIA feedforward neurocircuit (consisting of ADF, RIC, and SIA neurons) and ADF/RIC/AWB/ADF feedback neurocircuit (consisting of ADF, RIC, AWB, and ADF neurons) under conditions of food supply and food deprivation, respectively. Food supply stimulates food-sensing ADFs to release more 5-HT, which augments pumping via inhibiting OA secretion by RIC interneurons and, thus, alleviates pumping suppression by OA-activated SIA interneurons/motoneurons. In contrast, nutrient deprivation stimulates RICs to secrete OA, which suppresses pumping via activating SIAs and maintains basal pumping and 5-HT production activity through excitation of ADFs relayed by AWB sensory neurons. Notably, the feedforward and feedback circuits employ distinct modalities of neurosignal integration, namely, disinhibition and disexcitation, respectively.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Octopamina/farmacologia , Serotonina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Proteínas de Caenorhabditis elegans/fisiologia , Ingestão de Alimentos/fisiologia , Jejum/fisiologia , Privação de Alimentos/fisiologia , Interneurônios/patologia , Neurônios Motores/fisiologia , Células Receptoras Sensoriais/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
12.
Sci Rep ; 8(1): 3020, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445226

RESUMO

Ethanol is a widely used beverage and abused drug. Alcoholism causes severe damage to human health and creates serious social problems. Understanding the mechanisms underlying ethanol actions is important for the development of effective therapies. Alcohol has a wide spectrum of effects on physiological activities and behaviours, from sensitization to sedation and even intoxication with increasing concentrations. Animals develop tolerance to ethanol. However, the underlying mechanisms are not well understood. In Caenorhabditis elegans, NPR-1 negatively regulates the development of acute tolerance to ethanol. Here, using in vivo Ca2+ imaging, behavioural tests and chemogenetic manipulation, we show that the soluble guanylate cyclase complex GCY-35/GCY-36-TAX-2/TAX-4 signalling pathway in O2 sensory neurons positively regulates acute functional tolerance in npr-1 worms.


Assuntos
Tolerância a Medicamentos/fisiologia , Etanol/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Guanilato Ciclase/fisiologia , Proteínas Ativadoras de Guanilato Ciclase/metabolismo , Canais Iônicos/metabolismo , Oxigênio/metabolismo , Receptores de Neuropeptídeo Y/genética , Receptores de Neuropeptídeo Y/metabolismo , Células Receptoras Sensoriais/metabolismo , Transdução de Sinais/fisiologia
13.
Sci Rep ; 6: 19779, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26891989

RESUMO

Animals have developed the ability to sense the water content in their habitats, including hygrosensation (sensing humidity in the air) and hydrosensation (sensing the water content in other microenvironments), and they display preferences for specific water contents that influence their mating, reproduction and geographic distribution. We developed and employed four quantitative behavioural test paradigms to investigate the molecular and cellular mechanisms underlying sensing the water content in an agar substrate (hydrosensation) and hydrotaxis in Caenorhabditis elegans. By combining a reverse genetic screen with genetic manipulation, optogenetic neuronal manipulation and in vivo Ca(2+) imaging, we demonstrate that adult worms avoid the wetter areas of agar plates and hypo-osmotic water droplets. We found that the cGMP signalling pathway in ciliated sensory neurons is involved in hydrosensation and hydrotaxis in Caenorhabditis elegans.


Assuntos
Caenorhabditis elegans/fisiologia , GMP Cíclico/metabolismo , Sensação , Transdução de Sinais , Água , Animais , Comportamento Animal , Receptores Acoplados a Proteínas G/metabolismo , Células Receptoras Sensoriais/fisiologia
14.
Biochem Biophys Res Commun ; 461(3): 463-8, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25871795

RESUMO

The off-response of ASH neurons had been overlooked until the microfluidic devices were introduced for in vivo imaging of neuronal activity in Caenorhabditis elegans. The mechanisms of ASH off-response were completely unknown. Here we monitored ASH off-response to CuSO4 stimulation by use of microfluidic device and genetically encoded calcium indicator (GECI) - Case12. We found ASH neurons exhibited a multiphasic response to 10 mM and 50 mM CuSO4 of 30-s stimulation duration. ASH off-responding to Cu(2+) had been dramatically reduced in goa-1, mod-5, trpa-1 and egl-8 mutants. Moreover, in osm-9 mutants ASH off-response was completely eliminated. Neuron-specific rescue of osm-9 in ASH neurons restored the off-response and the normal avoidance behavior in worms.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neurônios/efeitos dos fármacos , Canais de Cátion TRPV/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Sulfato de Cobre/farmacologia , Neurônios/metabolismo , Neurônios/fisiologia
15.
Nat Commun ; 6: 5655, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25585042

RESUMO

Sensory modulation is essential for animal sensations, behaviours and survival. Peripheral modulations of nociceptive sensations and aversive behaviours are poorly understood. Here we identify a biased cross-inhibitory neural circuit between ASH and ASI sensory neurons. This inhibition is essential to drive normal adaptive avoidance of a CuSO4 (Cu(2+)) challenge in Caenorhabditis elegans. In the circuit, ASHs respond to Cu(2+) robustly and suppress ASIs via electro-synaptically exciting octopaminergic RIC interneurons, which release octopamine (OA), and neuroendocrinally inhibit ASI by acting on the SER-3 receptor. In addition, ASIs sense Cu(2+) and permit a rapid onset of Cu(2+)-evoked responses in Cu(2+)-sensitive ADF neurons via neuropeptides possibly, to inhibit ASHs. ADFs function as interneurons to mediate ASI inhibition of ASHs by releasing serotonin (5-HT) that binds with the SER-5 receptor on ASHs. This elaborate modulation among sensory neurons via reciprocal inhibition fine-tunes the nociception and avoidance behaviour.


Assuntos
Aprendizagem da Esquiva , Caenorhabditis elegans/fisiologia , Interneurônios/fisiologia , Neurônios/fisiologia , Nociceptividade/fisiologia , Transdução de Sinais/fisiologia , Animais , Comportamento Animal , Fenômenos Biomecânicos , Proteínas de Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Cobre/química , Sulfato de Cobre/química , Genótipo , Microscopia Confocal , Mutação , Neuropeptídeos/química , Nociceptores/metabolismo , Octopamina/química , Células Receptoras Sensoriais/fisiologia , Serotonina/química
16.
Biochem J ; 461(3): 509-20, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24854345

RESUMO

Lysosomes act as terminal degradation organelles to hydrolyse macromolecules derived from both the extracellular space and the cytoplasm. In Caenorhabditis elegans fasting induces the lysosomal compartment to expand. However, the molecular and cellular mechanisms for this stress response remain largely unclear. In the present study, we find that short-term fasting leads to increased accumulation of polar lipids in lysosomes. The fasting response is co-ordinately regulated by EGL-4, the C. elegans PKG (protein kinase G) orthologue, and nuclear hormone receptor NHR-49. Further results demonstrate that EGL-4 acts in sensory neurons to enhance lysosomal lipid accumulation through inhibiting the DAF-3/SMAD pathway, whereas NHR-49 acts in intestine to inhibit lipids accumulation via activation of IPLA-2 (intracellular membrane-associated calcium-independent phospholipase A2) in cytoplasm and other hydrolases in lysosomes. Remarkably, the lysosomal lipid accumulation is independent of autophagy and RAB-7-mediated endocytosis. Taken together, our results reveal a new mechanism for lysosomal lipid metabolism during the stress response, which may provide new clues for investigations of lysosome function in energy homoeostasis.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Metabolismo dos Lipídeos , Lisossomos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Estresse Fisiológico , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/ultraestrutura , Proteínas de Caenorhabditis elegans/agonistas , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Proteínas Quinases Dependentes de GMP Cíclico/genética , Ativação Enzimática , Jejum/efeitos adversos , Hidrolases/química , Hidrolases/genética , Hidrolases/metabolismo , Cinética , Lisossomos/ultraestrutura , Mutação , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosfolipases A2 Independentes de Cálcio/química , Fosfolipases A2 Independentes de Cálcio/genética , Fosfolipases A2 Independentes de Cálcio/metabolismo , Interferência de RNA , Receptores Citoplasmáticos e Nucleares/genética , Células Receptoras Sensoriais/enzimologia , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/ultraestrutura , Proteínas Smad/antagonistas & inibidores , Proteínas Smad/genética , Proteínas Smad/metabolismo , Regulação para Cima
17.
J Genet Genomics ; 40(9): 445-52, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-24053946

RESUMO

The first microRNA was discovered in Caenorhabditis elegans in 1993, and since then, thousands of microRNAs have been identified from almost all eukaryotic organisms examined. MicroRNAs function in many biological events such as cell fate determination, metabolism, apoptosis, and carcinogenesis. So far, more than 250 microRNAs have been identified in C. elegans; however, functions for most of these microRNAs are still unknown. A small number of C. elegans microRNAs are associated with known physiological roles such as developmental timing, cell differentiation, stress response, and longevity. In this review, we summarize known roles of microRNAs in neuronal differentiation and function of C. elegans, and discuss interesting perspectives for future studies.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/metabolismo , Animais , Apoptose , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Diferenciação Celular , Longevidade , MicroRNAs/genética , Sistema Nervoso/crescimento & desenvolvimento , RNA de Helmintos/genética , RNA de Helmintos/metabolismo , Estresse Fisiológico , Fatores de Tempo
18.
Nat Commun ; 3: 1073, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23011127

RESUMO

Food and other environmental factors affect gene expression and behaviour of animals. Differences in bacterial food affect the behaviour and longevity of Caenorhabditis elegans. However, no research has been carried out to investigate whether bacteria could utilize endogenous RNAs to affect C. elegans physiology. Here we show that two Escherichia coli endogenous noncoding RNAs, OxyS and DsrA, impact on the physiology of C. elegans. OxyS downregulates che-2, leading to impairment in C. elegans chemosensory behaviour and DsrA suppresses diacylglycerol lipase gene F42G9.6, leading to a decrease in longevity. We also examine some genes in the C. elegans RNA interference pathway for their possible involvement in the effects of OxyS and DsrA. Other bacteria, such as Bacillus mycoides, may also utilize its noncoding RNAs to interfere with gene expression in C. elegans. Our results demonstrate that E. coli noncoding RNAs can regulate gene expression and physiological conditions of C. elegans and indicate that noncoding RNAs might have interspecies ecological roles.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Escherichia coli/genética , RNA Bacteriano/farmacologia , RNA não Traduzido/farmacologia , Animais , Caenorhabditis elegans/fisiologia
19.
Biochem Biophys Res Commun ; 397(3): 526-31, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20515653

RESUMO

UNC-31 or its mammalian homologue, Ca(2+)-dependent activator protein for secretion (CAPS), is indispensable for exocytosis of dense core vesicle (DCV) and synaptic vesicle (SV). From N- to the C-terminus, UNC-31 contains putative functional domains, including dynactin 1 binding domain (DBD), C2, PH, (M)UNC-13 homology domain (MHD) and DCV binding domain (DCVBD), the last four we examined in this study. We employed UNC-31 null mutant C. elegans worms to examine whether UNC-31 functions could be rescued by ectopic expression of full length UNC-31 vs each of these four domain-deleted mutants. Full length UNC-31 cDNA rescued the phenotypes of C. elegans null mutants in response to Ca(2+)-elevation in ALA neurons. Surprisingly, MHD deletion also rescued UNC-31 exocytotic function in part because the relatively high Ca(2+) level (pre-flash Ca(2+) was 450 nM) used in the capacitance study could bypass the MHD defect. Nonetheless, the three other domain-truncation cDNAs had almost no rescue on Ca(2+) evoked secretion. Importantly, this genetic null mutant rescue strategy enabled physiological studies at levels of whole organism to single cells, such as locomotion assay, pharmacological study of neurotransmission at neuromuscular junction, in vivo neuropeptide release measurement and analysis of vesicular docking. Our results suggest that each of these UNC-31 domains support distinct sequential molecular actions of UNC-31 in vesicular exocytosis, including steps in vesicle tethering and docking that bridge vesicle with plasma membrane, and subsequently priming vesicle by initiating the formation of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) core complex.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Neurônios/metabolismo , Vesículas Secretórias/metabolismo , Transmissão Sináptica , Animais , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação ao Cálcio/genética , Exocitose , Estrutura Terciária de Proteína/genética , Deleção de Sequência
20.
Biochem Biophys Res Commun ; 395(1): 82-6, 2010 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-20350530

RESUMO

Fluorescent timers are useful tools for studying the spatial and temporal cellular or molecular events. Based on the trans-splicing mechanism in Caenorhabditis elegans, we constructed a "fluorescent timer" through bicistronic expression of two fluorescent proteins with different maturation times. When used in vivo, this "timer" changes its color over time and therefore can be used to monitor the activity of the targeted promoters in C. elegans. Using this "timer", we have successfully traced the time-dependent activity of myo-3 promoter which drives expression in body wall muscle and vulval muscle. We found that the myo-3 promoter started to be active about 7 h after egg-laying and sustained its activity in the following hatching process. We have also determined the myo-3 promoter activity during larval development by this "timer". We anticipate that more new "fluorescent timers" with variable time-resolution could be designed by bicistronic expression of different fluorescent protein pairs.


Assuntos
Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Proteínas de Fluorescência Verde/química , Proteínas Luminescentes/química , Músculos/embriologia , Proteínas Recombinantes de Fusão/química , Animais , Animais Geneticamente Modificados , Embrião não Mamífero/metabolismo , Fluorescência , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas Luminescentes/genética , Músculos/metabolismo , Regiões Promotoras Genéticas , RNA Líder para Processamento , Proteínas Recombinantes de Fusão/genética , Trans-Splicing
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