RESUMEN

4-Nitrophenol (4-NP), as a toxic and refractory pollutant, has generated significant concern due to its adverse effects. However, the potential toxic effects and mechanism remained unclear. In this study, the reproduction, development, locomotion and reactive oxygen species (ROS) production of Caenorhabditis elegans were investigated to evaluate the 4-NP toxicity. We used metabolomics to assess the potential damage mechanisms. The role of metabolites in mediating the relationship between 4-NP and phenotypes was examined by correlation and mediation analysis. 4-NP (8 ng/L and 8 µg/L) caused significant reduction of brood size, ovulation rate, total germ cells numbers, head thrashes and body bends, and an increase in ROS. However, the oosperm numbers in uterus, body length and body width were decreased in 8 µg/L. Moreover, 36 differential metabolites were enriched in the significant metabolic pathways, including lysine biosynthesis, ß-alanine metabolism, tryptophan metabolism, pentose phosphate pathway, pentose and glucuronate interconversions, amino sugar and nucleotide sugar metabolism, starch and sucrose metabolism, galactose metabolism, propanoate metabolism, glycerolipid metabolism, and estrogen signaling pathway. The mechanism of 4-NP toxicity was that oxidative stress caused by the perturbation of amino acid, which had effects on energy metabolism through disturbing carbohydrate and lipid metabolism, and finally affected the estrogen signaling pathway to exert toxic effects. Moreover, correlation and mediation analysis showed glycerol-3P, glucosamine-6P, glucosamine-1P, UDP-galactose, L-aspartic acid, and uracil were potential markers for the reproduction and glucose-1,6P2 for developmental toxicity. The results provided insight into the pathways involved in the toxic effects caused by 4-NP and developed potential biomarkers to evaluate 4-NP toxicity.

Asunto(s)

Caenorhabditis elegans , Estrógenos , Nitrofenoles , Reproducción , Transducción de Señal , Animales , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/fisiología , Reproducción/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Nitrofenoles/toxicidad , Estrógenos/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo/efectos de los fármacos

RESUMEN

BACKGROUND: Mutations in several genes of Caenorhabditis elegans confer altered sensitivities to volatile anesthetics. A mutation in one gene, gas-1(fc21), causes animals to be immobilized at lower concentrations of all volatile anesthetics than in the wild type, and it does not depend on mutations in other genes to control anesthetic sensitivity. gas-1 confers different sensitivities to stereoisomers of isoflurane, and thus may be a direct target for volatile anesthetics. The authors have cloned and characterized the gas gene and the mutant allele fc21. METHODS: Genetic techniques for nematodes were as previously described. Polymerase chain reaction, sequencing, and other molecular biology techniques were performed by standard methods. Mutant rescue was done by injecting DNA fragments into the gonad of mutant animals and scoring the offspring for loss of the mutant phenotype. RESULTS: The gas-1 gene was cloned and identified. The protein GAS-1 is a homologue of the 49-kd (IP) subunit of the mitochondrial NADH-ubiquinone-oxidoreductase (complex I of the respiratory chain). gas-1(fc21) is a missense mutation replacing a strictly conserved arginine with lysine. CONCLUSIONS: The function of the 49-kd (IP) subunit of complex I is unknown. The finding that mutations in complex I increase sensitivity of C. elegans to volatile anesthetics may implicate this physiologic process in the determination of anesthetic sensitivity. The hypersensitivity of animals with a mutation in the gas-1 gene may be caused by a direct anesthetic effect on a mitochondrial protein or secondary effects at other sites caused by mitochondrial dysfunction.

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/efectos de los fármacos , Proteínas de Caenorhabditis elegans/genética , Mutación , Anestésicos por Inhalación , Complejo I de Transporte de Electrón/genética , Complejo I de Transporte de Electrón/metabolismo , Secuencia de Aminoácidos , Isoflurano/farmacología

RESUMEN

Panax ginseng C. A. Meyer (ginseng) is a medicinal plant widely used for promoting longevity. Recently, homogalacturonan (HG) domain-rich pectins purified from some plants have been reported to have anti-aging-related activities, leading us to explore the longevity-promoting activity of the HG pectins from ginseng. In this study, we discovered that two of low methyl-esterified ginseng HG pectins (named as WGPA-2-HG and WGPA-3-HG), whose degree of methyl-esterification (DM) was 16 % and 8 % respectively, promoted longevity in Caenorhabditis elegans. Results showed that WGPA-2-HG/WGPA-3-HG impaired insulin/insulin-like growth factor 1 (IGF-1) signalling (IIS) pathway, thereby increasing the nuclear accumulation of transcription factors SKN-1/Nrf2 and DAF-16/FOXO and enhancing the expression of relevant anti-aging genes. BLI and ITC analysis showed that the insulin-receptor binding, the first step to activate IIS pathway, was impeded by the engagement of WGPA-2-HG/WGPA-3-HG with insulin. By chemical modifications, we found that high methyl-esterification of WGPA-2-HG/WGPA-3-HG was detrimental for their longevity-promoting activity. These findings provided novel insight into the precise molecular mechanism for the longevity-promoting effect of ginseng pectins, and suggested a potential to utilize the ginseng HG pectins with appropriate DM values as natural nutrients for increasing human longevity.

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Factor I del Crecimiento Similar a la Insulina , Insulina , Longevidad , Panax , Pectinas , Transducción de Señal , Animales , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Panax/química , Factor I del Crecimiento Similar a la Insulina/metabolismo , Pectinas/farmacología , Pectinas/metabolismo , Pectinas/química , Longevidad/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Insulina/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Esterificación

RESUMEN

Air-water interface (AWI) interactions during cryo-electron microscopy (cryo-EM) sample preparation cause significant sample loss, hindering structural biology research. Organisms like nematodes and tardigrades produce Late Embryogenesis Abundant (LEA) proteins to withstand desiccation stress. Here we show that these LEA proteins, when used as additives during plunge freezing, effectively mitigate AWI damage to fragile multi-subunit molecular samples. The resulting high-resolution cryo-EM maps are comparable to or better than those obtained using existing AWI damage mitigation methods. Cryogenic electron tomography reveals that particles are localized at specific interfaces, suggesting LEA proteins form a barrier at the AWI. This interaction may explain the observed sample-dependent preferred orientation of particles. LEA proteins offer a simple, cost-effective, and adaptable approach for cryo-EM structural biologists to overcome AWI-related sample damage, potentially revitalizing challenging projects and advancing the field of structural biology.

Asunto(s)

Aire , Microscopía por Crioelectrón , Congelación , Agua , Microscopía por Crioelectrón/métodos , Agua/química , Animales , Tomografía con Microscopio Electrónico/métodos , Caenorhabditis elegans

Asunto(s)

Caenorhabditis elegans , Calcio , Músculos , Animales , Caenorhabditis elegans/metabolismo , Calcio/metabolismo , Músculos/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Señalización del Calcio/fisiología

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Acoplamiento Excitación-Contracción/fisiología , Células Musculares/metabolismo , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo

RESUMEN

Measuring neuronal activity is important for understanding neuronal function. Ca2+ imaging by genetically encoded calcium indicators (GECIs) is a powerful way to measure neuronal activity. Although it revealed important aspects of neuronal function, measuring the neuronal membrane voltage is important to understand neuronal function as it triggers neuronal activation. Recent progress of genetically encoded voltage indicators (GEVIs) enabled us fast and precise measurements of neuronal membrane voltage. To clarify the relation of the membrane voltage and intracellular Ca2+, we analyzed neuronal activities of olfactory neuron AWA in Caenorhabditis elegans by GCaMP6f (GECI) and paQuasAr3 (GEVI) responding to odorants. We found that the membrane voltage encodes the stimuli change by the timing and the duration by the weak semi-stable depolarization. However, the change of the intracellular Ca2+ encodes the strength of the stimuli. Furthermore, ODR-3, a G-protein alpha subunit, was shown to be important for stabilizing the membrane voltage. These results suggest that the combination of calcium and voltage imaging provides a deeper understanding of the information in neural circuits.

Asunto(s)

Caenorhabditis elegans , Calcio , Animales , Caenorhabditis elegans/fisiología , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Calcio/metabolismo , Potenciales de la Membrana/fisiología , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Neuronas Receptoras Olfatorias/fisiología , Neuronas Receptoras Olfatorias/metabolismo , Odorantes/análisis

RESUMEN

When an organism encounters a pathogen, the host innate immune system activates to defend against pathogen colonization and toxic xenobiotics produced. C. elegans employ multiple defense systems to ensure survival when exposed to Pseudomonas aeruginosa including activation of the cytoprotective transcription factor SKN-1/NRF2. Although wildtype C. elegans quickly learn to avoid pathogens, here we describe a peculiar apathy-like behavior towards PA14 in animals with constitutive activation of SKN-1, whereby animals choose not to leave and continue to feed on the pathogen even when a non-pathogenic and healthspan-promoting food option is available. Although lacking the urgency to escape the infectious environment, animals with constitutive SKN-1 activity are not oblivious to the presence of the pathogen and display the typical pathogen-induced intestinal distension and eventual demise. SKN-1 activation, specifically in neurons and intestinal tissues, orchestrates a unique transcriptional program which leads to defects in serotonin signaling that is required from both neurons and non-neuronal tissues. Serotonin depletion from SKN-1 activation limits pathogen defenses capacity, drives the pathogen-associated apathy behaviors and induces a synthetic sensitivity to selective serotonin reuptake inhibitors. Taken together, our work reveals interesting insights into how animals perceive environmental pathogens and subsequently alter behavior and cellular programs to promote survival.

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Proteínas de Unión al ADN , Pseudomonas aeruginosa , Serotonina , Factores de Transcripción , Animales , Caenorhabditis elegans/microbiología , Caenorhabditis elegans/inmunología , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Pseudomonas aeruginosa/fisiología , Pseudomonas aeruginosa/patogenicidad , Serotonina/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Neuronas/metabolismo , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/metabolismo , Infecciones por Pseudomonas/microbiología , Inmunidad Innata , Transducción de Señal , Apatía/fisiología , Interacciones Huésped-Patógeno/inmunología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología

RESUMEN

Mitochondria exhibit a close interplay between their structure and function. Understanding this intricate relationship requires advanced imaging techniques that can capture the dynamic nature of mitochondria and their impact on cellular processes. However, much of the work on mitochondrial dynamics has been performed in single celled organisms or in vitro cell culture. Here, we introduce novel genetic tools for live imaging of mitochondrial morphology in the nematode Caenorhabditis elegans, addressing a pressing need for advanced techniques in studying organelle dynamics within live intact multicellular organisms. Through a comprehensive analysis, we directly compare our tools with existing methods, demonstrating their advantages for visualizing mitochondrial morphology and contrasting their impact on organismal physiology. We reveal limitations of conventional techniques, whereas showcasing the utility and versatility of our approaches, including endogenous CRISPR tags and ectopic labeling. By providing a guide for selecting the most suitable tools based on experimental goals, our work advances mitochondrial research in C. elegans and enhances the strategic integration of diverse imaging modalities for a holistic understanding of organelle dynamics in living organisms.

Asunto(s)

Caenorhabditis elegans , Mitocondrias , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Animales , Mitocondrias/metabolismo , Dinámicas Mitocondriales/fisiología

RESUMEN

Mechanical stress is a measure of internal resistance exhibited by a body or material when external forces, such as compression, tension, bending, etc. are applied. The study of mechanical stress on health and aging is a continuously growing field, as major changes to the extracellular matrix and cell-to-cell adhesions can result in dramatic changes to tissue stiffness during aging and diseased conditions. For example, during normal aging, many tissues including the ovaries, skin, blood vessels, and heart exhibit increased stiffness, which can result in a significant reduction in function of that organ. As such, numerous model systems have recently emerged to study the impact of mechanical and physical stress on cell and tissue health, including cell-culture conditions with matrigels and other surfaces that alter substrate stiffness and ex vivo tissue models that can apply stress directly to organs like muscle or tendons. Here, we sought to develop a novel method in an in vivo model organism setting to study the impact of altering substrate stiffness on aging by changing the stiffness of solid agar medium used for growth of C. elegans. We found that greater substrate stiffness had limited effects on cellular health, gene expression, organismal health, stress resilience, and longevity. Overall, our study reveals that altering substrate stiffness of growth medium for C. elegans has only mild impact on animal health and longevity; however, these impacts were not nominal and open up important considerations for C. elegans biologists in standardizing agar medium choice for experimental assays.

Asunto(s)

Caenorhabditis elegans , Longevidad , Animales , Caenorhabditis elegans/fisiología , Caenorhabditis elegans/crecimiento & desarrollo , Estrés Mecánico , Medios de Cultivo

RESUMEN

Spatially and temporally accurate termination of axon outgrowth, a process called axon termination, is required for efficient, precise nervous system construction and wiring. The mechanosensory neurons that sense low-threshold mechanical stimulation or gentle touch have proven exceptionally valuable for studying axon termination over the past 40 years. In this Review, we discuss progress made in deciphering the molecular and genetic mechanisms that govern axon termination in touch receptor neurons. Findings across model organisms, including Caenorhabditis elegans, Drosophila, zebrafish and mice, have revealed that complex signaling is required for termination with conserved principles and players beginning to surface. A key emerging theme is that axon termination is mediated by complex signaling networks that include ubiquitin ligase signaling hubs, kinase cascades, transcription factors, guidance/adhesion receptors and growth factors. Here, we begin a discussion about how these signaling networks could represent termination codes that trigger cessation of axon outgrowth in different species and types of mechanosensory neurons.

Asunto(s)

Axones , Transducción de Señal , Animales , Axones/metabolismo , Axones/fisiología , Mecanorreceptores/metabolismo , Caenorhabditis elegans/metabolismo , Drosophila/metabolismo

RESUMEN

Genetically modified organisms are commonly used in disease research and agriculture but the precise genomic alterations underlying transgenic mutations are often unknown. The position and characteristics of transgenes, including the number of independent insertions, influences the expression of both transgenic and wild-type sequences. We used long-read, Oxford Nanopore Technologies (ONT) to sequence and assemble two transgenic strains of Caenorhabditis elegans commonly used in the research of neurodegenerative diseases: BY250 (pPdat-1::GFP) and UA44 (GFP and human α-synuclein), a model for Parkinson's research. After scaffolding to the reference, the final assembled sequences were ∼102 Mb with N50s of 17.9 Mb and 18.0 Mb, respectively, and L90s of six contiguous sequences, representing chromosome-level assemblies. Each of the assembled sequences contained more than 99.2% of the Nematoda BUSCO genes found in the C. elegans reference and 99.5% of the annotated C. elegans reference protein-coding genes. We identified the locations of the transgene insertions and confirmed that all transgene sequences were inserted in intergenic regions, leaving the organismal gene content intact. The transgenic C. elegans genomes presented here will be a valuable resource for Parkinson's research as well as other neurodegenerative diseases. Our work demonstrates that long-read sequencing is a fast, cost-effective way to assemble genome sequences and characterize mutant lines and strains.

Asunto(s)

Animales Modificados Genéticamente , Caenorhabditis elegans , Secuenciación de Nanoporos , Transgenes , Caenorhabditis elegans/genética , Animales , Transgenes/genética , Animales Modificados Genéticamente/genética , Secuenciación de Nanoporos/métodos , alfa-Sinucleína/genética , Genoma de los Helmintos , Mutagénesis Insercional , Humanos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo

RESUMEN

How can inter-individual variability be quantified? Measuring many features per experiment raises the question of choosing them to recapitulate high-dimensional data. Tackling this challenge on spindle elongation phenotypes, we showed that only three typical elongation patterns describe spindle elongation in C. elegans one-cell embryo. These archetypes, automatically extracted from the experimental data using principal component analysis (PCA), accounted for more than 95% of inter-individual variability of more than 1600 experiments across more than 100 different conditions. The two first archetypes were related to spindle average length and anaphasic elongation rate. The third archetype, accounting for 6% of the variability, was novel and corresponded to a transient spindle shortening in late metaphase, reminiscent of kinetochore function-defect phenotypes. Importantly, these three archetypes were robust to the choice of the dataset and were found even considering only non-treated conditions. Thus, the inter-individual differences between genetically perturbed embryos have the same underlying nature as natural inter-individual differences between wild-type embryos, independently of the temperatures. We thus propose that beyond the apparent complexity of the spindle, only three independent mechanisms account for spindle elongation, weighted differently in the various conditions. Interestingly, the spindle-length archetypes covered both metaphase and anaphase, suggesting that spindle elongation in late metaphase is sufficient to predict the late anaphase length. We validated this idea using a machine-learning approach. Finally, given amounts of these three archetypes could represent a quantitative phenotype. To take advantage of this, we set out to predict interacting genes from a seed based on the PCA coefficients. We exemplified this firstly on the role of tpxl-1 whose homolog tpx2 is involved in spindle microtubule branching, secondly the mechanism regulating metaphase length, and thirdly the central spindle players which set the length at anaphase. We found novel interactors not in public databases but supported by recent experimental publications.

Asunto(s)

Caenorhabditis elegans , Fenotipo , Huso Acromático , Caenorhabditis elegans/embriología , Caenorhabditis elegans/fisiología , Caenorhabditis elegans/genética , Huso Acromático/fisiología , Animales , Análisis de Componente Principal , Biología Computacional , Embrión no Mamífero/embriología , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo

RESUMEN

The development of functional neurons is a complex orchestration of multiple signaling pathways controlling cell proliferation and differentiation. Because the balance of antioxidants is important for neuronal survival and development, we hypothesized that ferroptosis must be suppressed to gain neurons. We find that removal of antioxidants diminishes neuronal development and laminar organization of cortical organoids, which is fully restored when ferroptosis is inhibited by ferrostatin-1 or when neuronal differentiation occurs in the presence of vitamin A. Furthermore, iron-overload-induced developmental growth defects in C. elegans are ameliorated by vitamin E and A. We determine that all-trans retinoic acid activates the Retinoic Acid Receptor, which orchestrates the expression of anti-ferroptotic genes. In contrast, retinal and retinol show radical-trapping antioxidant activity. Together, our study reveals an unexpected function of vitamin A in coordinating the expression of essential cellular gatekeepers of ferroptosis, and demonstrates that suppression of ferroptosis by radical-trapping antioxidants or by vitamin A is required to obtain mature neurons and proper laminar organization in cortical organoids.

Asunto(s)

Antioxidantes , Caenorhabditis elegans , Ferroptosis , Neuronas , Vitamina A , Animales , Ferroptosis/efectos de los fármacos , Vitamina A/farmacología , Vitamina A/metabolismo , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efectos de los fármacos , Antioxidantes/farmacología , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Neuronas/citología , Ciclohexilaminas/farmacología , Diferenciación Celular/efectos de los fármacos , Vitamina E/farmacología , Receptores de Ácido Retinoico/metabolismo , Receptores de Ácido Retinoico/genética , Tretinoina/farmacología , Organoides/efectos de los fármacos , Organoides/metabolismo , Neurogénesis/efectos de los fármacos , Ratones , Humanos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Transducción de Señal/efectos de los fármacos , Fenilendiaminas

RESUMEN

Beta-amyloid (Aß), the most pivotal pathological hallmark for Alzheimer's disease (AD) diagnosis and drug evaluation, was recognized by TZ095, a high-affinity fluorescent probe developed by rational molecular design. With a TICT mechanism, TZ095 exhibited remarkable affinity with Aß aggregates (Kd = 81.54 nM for oligomers; Kd = 66.70 nM for fibril) and substantial fluorescence enhancement (F/F0 = 44), enabling real-time monitoring of Aß in live cells and nematodes. Significantly, this work used TZ095 to construct a new protocol that can quickly and conveniently monitor Aß changes at the cellular and nematode levels to evaluate the anti-AD efficacy of candidate compounds, and four reported Aß-lowering drug candidates were administrated for validation. Imaging data demonstrated that TZ095 can visually and quantitatively track the effect of Aß elimination after drug treatment. Furthermore, TZ095 excelled in ex vivo histological staining of 12-month-old APP/PS1 mouse brains, accurately visualizing Aß plaques. Integrating CUBIC technology, TZ095 facilitated whole-brain, 3D imaging of Aß distribution in APP/PS1 mice, enabling high-resolution in situ analysis of Aß plaques. Collectively, these innovative applications of TZ095 offer a promising strategy for rapid, convenient, and real-time monitoring of Aß levels in preclinical therapeutic assessments.

Asunto(s)

Enfermedad de Alzheimer , Péptidos beta-Amiloides , Diseño de Fármacos , Colorantes Fluorescentes , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Animales , Humanos , Ratones , Estructura Molecular , Ratones Transgénicos , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efectos de los fármacos , Relación Estructura-Actividad , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Relación Dosis-Respuesta a Droga , Imagen Óptica

RESUMEN

Detecting chemical signals is important for identifying food sources and avoiding harmful agents. Like many animals, C. elegans use olfaction to chemotax towards their main food source, bacteria. However, little is known about the bacterial compounds governing C. elegans attraction to bacteria and the physiological importance of these compounds to bacteria. Here, we address these questions by investigating the function of a small RNA, P11, in the pathogen, Pseudomonas aeruginosa, that was previously shown to mediate learned pathogen avoidance. We discovered that this RNA also affects the attraction of untrained C. elegans to P. aeruginosa and does so by controlling production of ammonia, a volatile odorant produced during nitrogen assimilation. We describe the complex regulation of P. aeruginosa nitrogen assimilation, which is mediated by a partner-switching mechanism involving environmental nitrates, sensor proteins, and P11. In addition to mediating C. elegans attraction, we demonstrate that nitrogen assimilation mutants perturb bacterial fitness and pathogenesis during C. elegans infection by P. aeruginosa. These studies define ammonia as a major mediator of trans-kingdom signaling, implicate nitrogen assimilation as important for both bacteria and host organisms, and highlight how a bacterial metabolic pathway can either benefit or harm a host in different contexts.

Asunto(s)

Amoníaco , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Nitrógeno , Pseudomonas aeruginosa , Caenorhabditis elegans/microbiología , Caenorhabditis elegans/metabolismo , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiología , Animales , Nitrógeno/metabolismo , Amoníaco/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/metabolismo , Nitratos/metabolismo , Transducción de Señal , Interacciones Huésped-Patógeno , Quimiotaxis

RESUMEN

Clerodendranthus spicatus (Thunb.) (Kidney tea) is a very distinctive ethnic herbal medicine in China. Its leaves are widely used as a healthy tea. Many previous studies have demonstrated its various longevity-promoting effects; however, the safety and specific health-promoting effects of Clerodendranthus spicatus (C. spicatus) as a dietary supplement remain unclear. In order to understand the effect of C. spicatus on the longevity of Caenorhabditis elegans (C. elegans), we evaluated its role in C. elegans; C. spicatus water extracts (CSw) were analyzed for the major components and the effects on C. elegans were investigated from physiological and biochemical to molecular levels; CSw contain significant phenolic components (primarily rosmarinic acid and eugenolinic acid) and flavonoids (primarily quercetin and isorhamnetin) and can increase the lifespan of C. elegans. Further investigations showed that CSw modulate stress resistance and lipid metabolism through influencing DAF-16/FoxO (DAF-16), Heat shock factor 1 (HSF-1), and Nuclear Hormone Receptor-49 (NHR-49) signalling pathways; CSw can improve the antioxidant and hypolipidemic activity of C. elegans and prolong the lifespan of C. elegans (with the best effect at low concentrations). Therefore, the recommended daily use of C. spicatus should be considered when consuming it as a healthy tea on a daily basis.

Asunto(s)

Caenorhabditis elegans , Metabolismo de los Lípidos , Estrés Oxidativo , Extractos Vegetales , Animales , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Metabolismo de los Lípidos/efectos de los fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Longevidad/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Antioxidantes/farmacología , Agua

RESUMEN

Glycation Stress (GS), induced by advanced glycation end-products (AGEs), significantly impacts aging processes. This study introduces a new model of GS of Caenorhabditis elegans by feeding them Escherichia coli OP50 cultured in a glucose-enriched medium, which better simulates human dietary glycation compared to previous single protein-glucose cross-linking methods. Utilizing WormCNN, a deep learning model, we assessed the health status and calculated the Healthy Aging Index (HAI) of worms with or without GS. Our results demonstrated accelerated aging in the GS group, evidenced by increased autofluorescence and altered gene expression of key aging regulators, daf-2 and daf-16. Additionally, we observed elevated pharyngeal pumping rates in AGEs-fed worms, suggesting an addictive response similar to human dietary patterns. This study highlights the profound effects of GS on worm aging and underscores the critical role of computer vision in accurately assessing health status and aiding in the establishment of disease models. The findings provide insights into glycation-induced aging and offer a comprehensive approach to studying the effects of dietary glycation on aging processes.

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Productos Finales de Glicación Avanzada , Animales , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Productos Finales de Glicación Avanzada/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Envejecimiento Saludable/metabolismo , Envejecimiento/metabolismo , Estrés Fisiológico , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Glicosilación , Glucosa/metabolismo , Modelos Animales de Enfermedad , Receptor de Insulina

RESUMEN

Although centrosomes help organize spindles in most cell types, oocytes of most species lack these structures. During acentrosomal spindle assembly in C. elegans oocytes, microtubule minus ends are sorted outwards away from the chromosomes where they form poles, but then these outward forces must be balanced to form a stable bipolar structure. Simultaneously, microtubule dynamics must be precisely controlled to maintain spindle length and organization. How forces and dynamics are tuned to create a stable bipolar structure is poorly understood. Here, we have gained insight into this question through studies of ZYG-8, a conserved doublecortin-family kinase; the mammalian homolog of this microtubule-associated protein is upregulated in many cancers and has been implicated in cell division, but the mechanisms by which it functions are poorly understood. We found that ZYG-8 depletion from oocytes resulted in overelongated spindles with pole and midspindle defects. Importantly, experiments with monopolar spindles revealed that ZYG-8 depletion led to excess outward forces within the spindle and suggested a potential role for this protein in regulating the force-generating motor BMK-1/kinesin-5. Further, we found that ZYG-8 is also required for proper microtubule dynamics within the oocyte spindle and that kinase activity is required for its function during both meiosis and mitosis. Altogether, our findings reveal new roles for ZYG-8 in oocytes and provide insights into how acentrosomal spindles are stabilized to promote faithful meiosis.

Asunto(s)

Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Microtúbulos , Oocitos , Huso Acromático , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiología , Microtúbulos/metabolismo , Microtúbulos/genética , Huso Acromático/metabolismo , Huso Acromático/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Oocitos/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Centrosoma/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética

RESUMEN

The transition of the sexual mode occurs widely in animal evolution. In Caenorhabditis nematodes, androdioecy, a sexual polymorphism composed of males and hermaphrodites having the ability to self-fertilize, has evolved independently multiple times. While the modification of noncoding regulatory elements likely contributed to the evolution of hermaphroditism, little is known about these changes. Here, we conducted a genome-wide analysis of conserved noncoding elements (CNEs) focusing on the evolution of hermaphroditism in Caenorhabditis nematodes. We found that, in androdioecious nematodes, mutations rapidly accumulated in CNEs' neighboring genes associated with sexual traits. Expression analysis indicate that the identified CNEs are involved in spermatogenesis in hermaphrodites and associated with the transition of gene expression from dioecious to androdioecious nematodes. Last, genome editing of a CNE neighboring laf-1 resulted in a change in its expression in the gonadal region undergoing spermatogenesis. Our bioinformatic and experimental analyses highlight the importance of CNEs in gene regulation associated with the development of hermaphrodites.

Asunto(s)

Evolución Molecular , Espermatogénesis , Animales , Masculino , Espermatogénesis/genética , Caenorhabditis/genética , Secuencia Conservada , Caenorhabditis elegans/genética , Evolución Biológica , Mutación , Femenino , Organismos Hermafroditas/genética , Regulación de la Expresión Génica