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PACS (phosphofurin acidic cluster sorting) proteins are known for their roles in sorting cargo proteins to organelles and can physically interact with WD40 repeat-containing protein WDR37. PACS1, PACS2, and WDR37 variants are associated with multisystemic syndromes and neurodevelopmental disorders characterized by intellectual disability, seizures, developmental delays, craniofacial abnormalities, and autism spectrum disorder. However, the functional effects of syndromic variants at the cellular level remain unknown. Here, we report the expression pattern of Caenorhabditis elegans orthologs of PACS and WDR37 and their interaction. We show that cePACS-1 and ceWDR-37 colocalize to somatic cytoplasm of many types of cells and are mutually required for expression, supporting a conclusion that the intermolecular dependence of PACS1/PACS2/PACS-1 and WDR37/WDR-37 is evolutionarily conserved. We further show that editing in PACS1 and PACS2 variants in cePACS-1 changes protein localization in multiple cell types, including neurons. Moreover, expression of human PACS1 can functionally complement C. elegans PACS-1 in neurons, demonstrating conserved functions of the PACS-WDR37 axis in an invertebrate model system. Our findings reveal effects of human variants and suggest potential strategies to identify regulatory network components that may contribute to understanding molecular underpinnings of PACS/WDR37 syndromes.

Although the molecular composition and architecture of synapses have been widely explored, much less is known about what genetic programs directly activate synaptic gene expression and how they are modulated. Here, using Caenorhabditis elegans dopaminergic neurons, we reveal that EGL-43/MECOM and FOS-1/FOS control an activity-dependent synaptogenesis program. Loss of either factor severely reduces presynaptic protein expression. Both factors bind directly to promoters of synaptic genes and act together with CUT homeobox transcription factors to activate transcription. egl-43 and fos-1 mutually promote each others expression, and increasing the binding affinity of FOS-1 to the egl-43 locus results in increased presynaptic protein expression and synaptic function. EGL-43 regulates the expression of multiple transcription factors, including activity-regulated factors and developmental factors that define multiple aspects of dopaminergic identity. Together, we describe a robust genetic program underlying activity-regulated synapse formation during development.

In many animal species, the oocyte meiotic spindle, which is required for chromosome segregation, forms without centrosomes. In some systems, Ran-GEF on chromatin initiates spindle assembly. We found that in Caenorhabditis elegans oocytes, endogenously-tagged Ran-GEF dissociates from chromatin during spindle assembly but re-associates during meiotic anaphase. Meiotic spindle assembly occurred after auxin-induced degradation of Ran-GEF, but anaphase I was faster than controls and extrusion of the first polar body frequently failed. In search of a possible alternative pathway for spindle assembly, we found that soluble tubulin concentrates in the nuclear volume during germinal vesicle breakdown. We found that the concentration of soluble tubulin in the metaphase spindle region is enclosed by ER sheets which exclude cytoplasmic organelles including mitochondria and yolk granules. Measurement of the volume occupied by yolk granules and mitochondria indicated that volume exclusion would be sufficient to explain the concentration of tubulin in the spindle volume. We suggest that this concentration of soluble tubulin may be a redundant mechanism promoting spindle assembly near chromosomes.

Protein translation initiation is a conserved process involving many proteins acting in concert. The 13 subunit eukaryotic initiation factor 3 (eIF3) complex is essential for assembly of the pre-initiation complex that scans mRNA and positions ribosome at the initiation codon. We previously reported that a gain-of-function (gf) mutation affecting the G subunit of the Caenorhabditis elegans eIF3 complex, eif-3.g(gf), selectively modulates protein translation in the ventral cord cholinergic motor neurons. Here, through unbiased genetic suppressor screening, we identified that the gene lin-66 mediates eif-3.g(gf)-dependent protein translation in motor neurons. LIN-66 is composed largely of low-complexity amino acid sequences with unknown functional domains. We combined bioinformatics analysis with in vivo functional dissection and identified a cold-shock domain in LIN-66 critical for its function. In cholinergic motor neurons, LIN-66 shows a close association with EIF-3.G in the cytoplasm. The low-complexity amino acid sequences of LIN-66 modulate its subcellular pattern. As cold-shock domains function broadly in RNA regulation, we propose that LIN-66 mediates stimulus-dependent protein translation by facilitating the interaction of mRNAs with EIF-3.G.

Upon sensing viral RNA, mammalian RIG-I-like receptors (RLRs) activate downstream signals using caspase activation and recruitment domains (CARDs), which ultimately promote transcriptional immune responses that have been well studied. In contrast, the downstream signaling mechanisms for invertebrate RLRs are much less clear. For example, the Caenorhabditis elegans RLR DRH-1 lacks annotated CARDs and up-regulates the distinct output of RNA interference. Here, we found that similar to mammal RLRs, DRH-1 signals through two tandem CARDs (2CARD) to induce a transcriptional immune response. Expression of DRH-1(2CARD) alone in the intestine was sufficient to induce immune gene expression, increase viral resistance, and promote thermotolerance, a phenotype previously associated with immune activation in C. elegans. We also found that DRH-1 is required in the intestine to induce immune gene expression, and we demonstrate subcellular colocalization of DRH-1 puncta with double-stranded RNA inside the cytoplasm of intestinal cells upon viral infection. Altogether, our results reveal mechanistic and spatial insights into antiviral signaling in C. elegans, highlighting unexpected parallels in RLR signaling between C. elegans and mammals.

During mitosis, the Bub1-Bub3 complex concentrates at kinetochores, the microtubule-coupling interfaces on chromosomes, where it contributes to spindle checkpoint activation, kinetochore-spindle microtubule interactions, and protection of centromeric cohesion. Bub1 has a conserved N-terminal tetratricopeptide repeat (TPR) domain followed by a binding motif for its conserved interactor Bub3. The current model for Bub1-Bub3 localization to kinetochores is that Bub3, along with its bound motif from Bub1, recognizes phosphorylated MELT motifs in the kinetochore scaffold protein Knl1. Motivated by the greater phenotypic severity of BUB-1 versus BUB-3 loss in C. elegans, we show that the BUB-1 TPR domain directly recognizes a distinct class of phosphorylated motifs in KNL-1 and that this interaction is essential for BUB-1-BUB-3 localization and function. BUB-3 recognition of phospho-MELT motifs additively contributes to drive super-stoichiometric accumulation of BUB-1-BUB-3 on its KNL-1 scaffold during mitotic entry. Bub1s TPR domain interacts with Knl1 in other species, suggesting that collaboration of TPR-dependent and Bub3-dependent interfaces in Bub1-Bub3 localization and functions may be conserved.

The central nervous system coordinates peripheral cellular stress responses, including the unfolded protein response of the mitochondria (UPRMT); however, the contexts for which this regulatory capability evolved are unknown. UPRMT is up-regulated upon pathogenic infection and in metabolic flux, and the olfactory nervous system has been shown to regulate pathogen resistance and peripheral metabolic activity. Therefore, we asked whether the olfactory nervous system in Caenorhabditis elegans controls the UPRMT cell nonautonomously. We found that silencing a single inhibitory olfactory neuron pair, AWC, led to robust induction of UPRMT and reduction of oxidative phosphorylation dependent on serotonin signaling and parkin-mediated mitophagy. Further, AWC ablation confers resistance to the pathogenic bacteria Pseudomonas aeruginosa partially dependent on the UPRMT transcription factor atfs-1 and fully dependent on mitophagy machinery. These data illustrate a role for the olfactory nervous system in regulating whole-organism mitochondrial dynamics, perhaps in preparation for postprandial metabolic stress or pathogenic infection.

Heat shock can be a lethal stressor. Previously, we described a CUL-6/cullin-ring ubiquitin ligase complex in the nematode Caenorhabditis elegans that is induced by intracellular intestinal infection and proteotoxic stress and that promotes improved survival upon heat shock (thermotolerance). Here, we show that CUL-6 promotes thermotolerance by targeting the heat shock protein HSP-90 for degradation. We show that CUL-6-mediated lowering of HSP-90 protein levels, specifically in the intestine, improves thermotolerance. Furthermore, we show that lysosomal function is required for CUL-6-mediated promotion of thermotolerance and that CUL-6 directs HSP-90 to lysosome-related organelles upon heat shock. Altogether, these results indicate that a CUL-6 ubiquitin ligase promotes organismal survival upon heat shock by promoting HSP-90 degradation in intestinal lysosomes. Thus, HSP-90, a protein commonly associated with protection against heat shock and promoting degradation of other proteins, is itself degraded to protect against heat shock.

Circadian rhythms are endogenous oscillations in nearly all organisms, from prokaryotes to humans, allowing them to adapt to cyclical environments for close to 24 h. Circadian rhythms are regulated by a central clock, based on a transcription-translation feedback loop. One important protein in the central loop in metazoan clocks is PERIOD, which is regulated in part by Casein kinase 1ε/δ (CK1ε/δ) phosphorylation. In the nematode Caenorhabditis elegans, period and casein kinase 1ε/δ are conserved as lin-42 and kin-20, respectively. Here, we studied the involvement of lin-42 and kin-20 in the circadian rhythms of the adult nematode using a bioluminescence-based circadian transcriptional reporter. We show that mutations of lin-42 and kin-20 generate a significantly longer endogenous period, suggesting a role for both genes in the nematode circadian clock, as in other organisms. These phenotypes can be partially rescued by overexpression of either gene under their native promoter. Both proteins are expressed in neurons and epidermal seam cells, as well as in other cells. Depletion of LIN-42 and KIN-20, specifically in neuronal cells after development, was sufficient to lengthen the period of oscillating sur-5 expression. Therefore, we conclude that LIN-42 and KIN-20 are critical regulators of the adult nematode circadian clock through neuronal cells.

Reproduction is a functional outcome that relies on complex cellular, tissue, and organ interactions that span the developmental period to adulthood. Thus, the assessment of its disruption by environmental chemicals would benefit significantly from scalable and innovative approaches to testing using functionally comparable reproductive models such as the nematode C. elegans. We adapted a previously described low-throughput in vivo chromosome segregation assay using C. elegans predictive of reproductive toxicity and leveraged available public data sources (ToxCast, ICE) to screen and characterize 133 physiologically-relevant chemicals in a high-throughput manner. The screening outcome was further validated in a second, independent in vivo assay assessing embryonic viability. In total, 13 chemicals were classified as reproductive toxicants with the two most active chemicals belonging to the large family of Quaternary Ammonium Compounds (QACs) commonly used as disinfectants but with limited available reproductive toxicity data. We compared the results from the C. elegans assay with ToxCast in vitro data compiled from 700+ cell response assays and 300+ signaling pathways-based assays. We did not observe a difference in the bioactivity or in the average potency (AC50) between the top and bottom chemicals. However, the intended target categories were significantly different between the classified chemicals with, in particular, an over-representation of steroid hormone targets for the high Z-score chemicals. Taken together, these results point to the value of in vivo models that scale to high-throughput level for reproductive toxicity assessment and to the need to prioritize the assessment of QACs impacts on reproduction.

In spliceosome assembly, the 5 splice site is initially recognized by U1 snRNA. U1 leaves the spliceosome during the assembly process, therefore other factors contribute to the maintenance of 5 splice site identity as it is loaded into the catalytic site. Recent structural data suggest that human tri-snRNP 27K (SNRP27) M141 and SNU66 H734 interact to stabilize the U4/U6 quasi-pseudo knot at the base of the U6 snRNA ACAGAGA box in pre-B complex. Previously, we found that mutations in Caenorhabditis elegans at SNRP-27 M141 promote changes in alternative 5ss usage. We tested whether the potential interaction between SNRP-27 M141 and SNU-66 H765 (the C. elegans equivalent position to human SNU66 H734) contributes to maintaining 5 splice site identity during spliceosome assembly. We find that SNU-66 H765 mutants promote alternative 5 splice site usage. Many of the alternative 5 splicing events affected by SNU-66(H765G) overlap with those affected SNRP-27(M141T). Double mutants of snrp-27(M141T) and snu-66(H765G) are homozygous lethal. We hypothesize that mutations at either SNRP-27 M141 or SNU-66 H765 allow the spliceosome to load alternative 5 splice sites into the active site. Tests with mutant U1 snRNA and swapped 5 splice sites indicate that the ability of SNRP-27 M141 and SNU-66 H765 mutants to affect a particular 5 splice alternative splicing event is dependent on both the presence of a weaker consensus 5ss nearby and potentially nearby splicing factor binding sites. Our findings confirm a new role for the C terminus of SNU-66 in maintenance of 5 splice site identity during spliceosome assembly.

The Alliance of Genome Resources (Alliance) is an extensible coalition of knowledge bases focused on the genetics and genomics of intensively studied model organisms. The Alliance is organized as individual knowledge centers with strong connections to their research communities and a centralized software infrastructure, discussed here. Model organisms currently represented in the Alliance are budding yeast, Caenorhabditis elegans, Drosophila, zebrafish, frog, laboratory mouse, laboratory rat, and the Gene Ontology Consortium. The project is in a rapid development phase to harmonize knowledge, store it, analyze it, and present it to the community through a web portal, direct downloads, and application programming interfaces (APIs). Here, we focus on developments over the last 2 years. Specifically, we added and enhanced tools for browsing the genome (JBrowse), downloading sequences, mining complex data (AllianceMine), visualizing pathways, full-text searching of the literature (Textpresso), and sequence similarity searching (SequenceServer). We enhanced existing interactive data tables and added an interactive table of paralogs to complement our representation of orthology. To support individual model organism communities, we implemented species-specific landing pages and will add disease-specific portals soon; in addition, we support a common community forum implemented in Discourse software. We describe our progress toward a central persistent database to support curation, the data modeling that underpins harmonization, and progress toward a state-of-the-art literature curation system with integrated artificial intelligence and machine learning (AI/ML).

Insulin-mechanistic target of rapamycin (mTOR) signaling drives anabolic growth during organismal development; its late-life dysregulation contributes to aging and limits lifespans. Age-related regulatory mechanisms and functional consequences of insulin-mTOR remain incompletely understood. Here, we identify LPD-3 as a megaprotein that orchestrates the tempo of insulin-mTOR signaling during C. elegans aging. We find that an agonist insulin, INS-7, is drastically overproduced from early life and shortens lifespan in lpd-3 mutants. LPD-3 forms a bridge-like tunnel megaprotein to facilitate non-vesicular cellular lipid trafficking. Lipidomic profiling reveals increased hexaceramide species in lpd-3 mutants, accompanied by up-regulation of hexaceramide biosynthetic enzymes, including HYL-1. Reducing the abundance of HYL-1, insulin receptor/DAF-2 or mTOR/LET-363, normalizes INS-7 levels and rescues the lifespan of lpd-3 mutants. LPD-3 antagonizes SINH-1, a key mTORC2 component, and decreases expression with age. We propose that LPD-3 acts as a megaprotein brake for organismal aging and that its age-dependent decline restricts lifespan through the sphingolipid-hexaceramide and insulin-mTOR pathways.

An animals preference for many chemosensory cues remains constant despite dramatic changes in the animals internal state. The mechanisms that maintain chemosensory preference across different physiological contexts remain poorly understood. We previously showed that distinct patterns of neural activity and motor output are evoked by carbon dioxide (CO2) in starved adults vs dauers of Caenorhabditis elegans, despite the two life stages displaying the same preference (attraction) for CO2. However, how the distinct CO2-evoked neural dynamics and motor patterns contribute to CO2 attraction at the two life stages remained unclear. Here, using a CO2 chemotaxis assay, we show that different interneurons are employed to drive CO2 attraction at the two life stages. We also investigate the molecular mechanisms that mediate CO2 attraction in dauers vs adults. We show that insulin signaling promotes CO2 attraction in dauers but not starved adults and that different combinations of neurotransmitters and neuropeptides are used for CO2 attraction at the two life stages. Our findings provide new insight into the distinct molecular and cellular mechanisms used by C. elegans at two different life stages to generate attractive behavioral responses to CO2.

Early-life stress experiences can produce lasting impacts on organismal adaptation and fitness. How transient stress elicits memory-like physiological effects is largely unknown. Here, we show that early-life thermal stress strongly up-regulates tsp-1, a gene encoding the conserved transmembrane tetraspanin in C. elegans. TSP-1 forms prominent multimers and stable web-like structures critical for membrane barrier functions in adults and during aging. Increased TSP-1 abundance persists even after transient early-life heat stress. Such regulation requires CBP-1, a histone acetyltransferase that facilitates initial tsp-1 transcription. Tetraspanin webs form regular membrane structures and mediate resilience-promoting effects of early-life thermal stress. Gain-of-function TSP-1 confers marked C. elegans longevity extension and thermal resilience in human cells. Together, our results reveal a cellular mechanism by which early-life thermal stress produces long-lasting memory-like impact on organismal resilience and longevity.

Progranulin is an evolutionarily conserved protein that has been implicated in human neurodevelopmental and neurodegenerative diseases. Human progranulin is comprised of multiple cysteine-rich, biologically active granulin peptides. Granulin peptides accumulate with age and stress, however their functional contributions relative to full-length progranulin remain unclear. To address this, we generated C. elegans strains that produced quantifiable levels of both full-length progranulin/PGRN-1 protein and cleaved granulin peptide. Using these strains, we demonstrated that even in the presence of intact PGRN-1, granulin peptides suppressed the activity of the lysosomal aspartyl protease activity, ASP-3/CTSD. Granulin peptides were also dominant over PGRN-1 in compromising animal fitness as measured by progress through development and stress response. Finally, the degradation of human TDP-43 was impaired when the granulin to PGRN-1 ratio was increased, representing a disease-relevant downstream impact of impaired lysosomal function. In summary, these studies suggest that not only absolute progranulin levels, but also the balance between full-length progranulin and its cleavage products, is important in regulating lysosomal biology. Given its relevance in human disease, this suggests that the processing of progranulin into granulins should be considered as part of disease pathobiology and may represent a site of therapeutic intervention.

Dysfunctional extracellular matrices (ECM) contribute to aging and disease. Repairing dysfunctional ECM could potentially prevent age-related pathologies. Interventions promoting longevity also impact ECM gene expression. However, the role of ECM composition changes in healthy aging remains unclear. Here we perform proteomics and in-vivo monitoring to systematically investigate ECM composition (matreotype) during aging in C. elegans revealing three distinct collagen dynamics. Longevity interventions slow age-related collagen stiffening and prolong the expression of collagens that are turned over. These prolonged collagen dynamics are mediated by a mechanical feedback loop of hemidesmosome-containing structures that span from the exoskeletal ECM through the hypodermis, basement membrane ECM, to the muscles, coupling mechanical forces to adjust ECM gene expression and longevity via the transcriptional co-activator YAP-1 across tissues. Our results provide in-vivo evidence that coordinated ECM remodeling through mechanotransduction is required and sufficient to promote longevity, offering potential avenues for interventions targeting ECM dynamics.

Fertilization occurs before the completion of oocyte meiosis in the majority of animal species and sperm contents move long distances within the zygotes of mouse and C. elegans. If incorporated into the meiotic spindle, paternal chromosomes could be expelled into a polar body resulting in lethal monosomy. Through live imaging of fertilization in C. elegans, we found that the microtubule disassembling enzymes, katanin and kinesin-13 limit long-range movement of sperm contents and that maternal ataxin-2 maintains paternal DNA and paternal mitochondria as a cohesive unit that moves together. Depletion of katanin or double depletion of kinesin-13 and ataxin-2 resulted in the capture of the sperm contents by the meiotic spindle. Thus limiting movement of sperm contents and maintaining cohesion of sperm contents within the zygote both contribute to preventing premature interaction between maternal and paternal genomes.

Protein quality control pathways play important roles in resistance against pathogen infection. For example, the conserved transcription factor SKN-1/NRF up-regulates proteostasis capacity after blockade of the proteasome and also promotes resistance against bacterial infection in the nematode Caenorhabditis elegans. SKN-1/NRF has 3 isoforms, and the SKN-1A/NRF1 isoform, in particular, regulates proteasomal gene expression upon proteasome dysfunction as part of a conserved bounce-back response. We report here that, in contrast to the previously reported role of SKN-1 in promoting resistance against bacterial infection, loss-of-function mutants in skn-1a and its activating enzymes ddi-1 and png-1 show constitutive expression of immune response programs against natural eukaryotic pathogens of C. elegans. These programs are the oomycete recognition response (ORR), which promotes resistance against oomycetes that infect through the epidermis, and the intracellular pathogen response (IPR), which promotes resistance against intestine-infecting microsporidia. Consequently, skn-1a mutants show increased resistance to both oomycete and microsporidia infections. We also report that almost all ORR/IPR genes induced in common between these programs are regulated by the proteasome and interestingly, specific ORR/IPR genes can be induced in distinct tissues depending on the exact trigger. Furthermore, we show that increasing proteasome function significantly reduces oomycete-mediated induction of multiple ORR markers. Altogether, our findings demonstrate that proteasome regulation keeps innate immune responses in check in a tissue-specific manner against natural eukaryotic pathogens of the C. elegans epidermis and intestine.

Caenorhabditis elegans is highly important in current research, serving as a pivotal model organism that has greatly advanced the understanding of fundamental biological processes such as development, cellular biology, and neurobiology, helping to promote major advances in various fields of science. In this context, the survival of a nematode under various conditions is commonly investigated via statistical survival analysis, which is typically based on hypothesis testing, providing valuable insights into the factors influencing its longevity and response to various environmental factors. The extensive reliance on hypothesis testing is acknowledged as a concern in the scientific analysis process, emphasizing the need for a comprehensive evaluation of alternative statistical approaches to ensure a rigorous and unbiased interpretation of research findings. In this work, we propose an alternative method to hypothesis testing for evaluating differences in nematode survival. Our approach relies on a clustering technique that takes into account the complete structure of survival curves, enabling a more comprehensive assessment of survival dynamics. The proposed methodology helps to identify complex effects on nematode survival and enables us to derive the probability that treatment induces a specific effect. To highlight the application and benefits of the proposed methodology, it is applied to two different datasets, one simple and one more complex. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increased activity of the heat shock factor, HSF-1, suppresses proteotoxicity and enhances longevity. However, the precise mechanisms by which HSF-1 promotes lifespan are unclear. Using an RNAi screen, we identify ubiquilin-1 (ubql-1) as an essential mediator of lifespan extension in worms overexpressing hsf-1. We find that hsf-1 overexpression leads to transcriptional downregulation of all components of the CDC-48-UFD-1-NPL-4 complex, which is central to both endoplasmic reticulum and mitochondria associated protein degradation, and that this is complemented by UBQL-1-dependent turnover of NPL-4.1. As a consequence, mitochondrial network dynamics are altered, leading to increased lifespan. Together, our data establish that HSF-1 mediates lifespan extension through mitochondrial network adaptations that occur in response to down-tuning of components associated with organellar protein degradation pathways. Increased activity of heat shock factor 1 (HSF1) promotes longevity; however, the mechanisms underlying this are unclear. Here, the authors show that in the nematode worm Caenorhabditis elegans, HSF1 overexpression increases lifespan through ubiquilin-1-dependent mitochondrial network remodelling. [ABSTRACT FROM AUTHOR]

Introduction: Diabesity, characterized by obesity-driven Type 2 diabetes mellitus (T2DM), arises from intricate genetic and environmental interplays that induce various metabolic disorders. The systemic lipid and glucose homeostasis is controlled by an intricate cross-talk of internal glucose/insulin and fatty acid molecules to maintain a steady state of internal environment. Methods: In this study, Caenorhabditis elegans were maintained to achieve glucose concentrations resembling the hyperglycemic conditions in diabetic patients to delve into the mechanistic foundations of diabesity. Various assays were conducted to measure intracellular triglyceride levels, lifespan, pharyngeal pumping rate, oxidative stress indicators, locomotor behavior, and dopamine signaling. Proteomic analysis was also performed to identify differentially regulated proteins and dysregulated KEGG pathways, and microscopy and immunofluorescence staining were employed to assess collagen production and anatomical integrity. Results: Worms raised on diets high in glucose and cholesterol exhibited notably increased intracellular triglyceride levels, a decrease in both mean and maximum lifespan, and reduced pharyngeal pumping. The diabesity condition induced oxidative stress, evident from heightened ROS levels and distinct FT-IR spectroscopy patterns revealing lipid and protein alterations. Furthermore, impaired dopamine signaling and diminished locomotors behavior in diabesity-afflicted worms correlated with reduced motility. Through proteomic analysis, differentially regulated proteins encompassing dysregulated KEGG pathways included insulin signaling, Alzheimer's disease, and nicotinic acetylcholine receptor signaling pathways were observed. Moreover, diabesity led to decreased collagen production, resulting in anatomical disruptions validated through microscopy and immunofluorescence staining. Discussion: This underscores the impact of diabesity on cellular components and structural integrity in C. elegans , providing insights into diabesity-associated mechanisms. [ABSTRACT FROM AUTHOR]

This study reports the development of new probes RR1 ((1E)-1-(1-(6-bromo-2-oxo-2H-chromen-3-yl)ethylidene)ethyl thiosemicarbazone) and RR2 ((1E)-1-(1-(6-bromo-2-oxo-2H-chromen-3-yl)ethylidene)phenyl thiosemicarbazone), which selectively showed fluorescence turn 'OFF' response towards Cu2+ and Al3+. Further, complexes of RR1-Cu2+ and RR2-Al3+ acted as chemosensors for the detection of L -amino acids. RR1-Cu2+ selectively detected L -arginine (fluorescence turn 'ON'), and RR2-Al3+ selectively detected L -glutamic acid (fluorescence turn 'ON'). The existence of the fluorophore–quencher complexes RR1-Cu2+ and RR2-Al3+ was confirmed by theoretical studies. Further, the chemosensors RR1-Cu2+ and RR2-Al3+ have three possible structural isomers (RR1-Cu2+- L -arginine – A, B and C) and (R2-Al3+- L -glutamic acid – D, E and F), as confirmed by theoretical studies. In vitro bio-imaging of the probes (RR1 and RR2), complexes (RR1-Cu2+ and RR2-Al3+) and complexes associated with L -arginine (RR1-Cu2+- L -arginine) and L -glutamic acid (R2-Al3+- L -glutamic acid) was performed in the MDA-MB-231 cell line using their IC50 concentrations. In addition, in vivo live cell imaging studies were conducted using C. elegans as the model organism. [ABSTRACT FROM AUTHOR]

The factors contributing to evolution of androdioecy, the coexistence of hermaphrodites and males such as in Caenorhabditis elegans, remains poorly known. However, nematodes exhibit androdioecy in at last 13 genera with the predatory genus Pristionchus having seven independent transitions towards androdioecy. Nonetheless, associated genomic architecture and sex determination mechanisms are largely known from Caenorhabditis. Here, studying 47 Pristionchus species, we observed repeated chromosome evolution which abolished the ancestral XX/XO sex chromosome system. Two phylogenetically unrelated androdioecious Pristionchus species have no genomic differences between sexes and mating hermaphrodites with males resulted in hermaphroditic offspring only. We demonstrate that stochastic sex determination is influenced by temperature in P. mayeri and P. entomophagus, and CRISPR engineering indicated a conserved role of the transcription factor TRA-1 in P. mayeri. Chromosome-level genome assemblies and subsequent genomic analysis of related Pristionchus species revealed stochastic sex determination to be derived from XY sex chromosome systems through sex chromosome-autosome fusions. Thus, rapid karyotype evolution, sex chromosome evolution and evolvable sex determination mechanisms are general features of this genus, and represent a dynamic background against which androdioecy has evolved recurrently. Future studies might indicate that stochastic sex determination is more common than currently appreciated. Sexual systems evolve frequently in nematodes. Through large-scale genomic analyses, Yoshida et al. find rapid chromosome evolution, sex chromosome turnover and acquisition of stochastic sex determination, are involved in sexual system evolution of Pristionchus nematodes. [ABSTRACT FROM AUTHOR]

Mitosis in early embryos often proceeds at a rapid pace, but how this pace is achieved is not understood. Here, we show that cyclin B3 is the dominant driver of rapid embryonic mitoses in the C. elegans embryo. Cyclins B1 and B2 support slow mitosis (NEBD to anaphase ~600 s), but the presence of cyclin B3 dominantly drives the approximately threefold faster mitosis observed in wildtype. Multiple mitotic events are slowed down in cyclin B1 and B2-driven mitosis, and cyclin B3-associated Cdk1 H1 kinase activity is ~25-fold more active than cyclin B1-associated Cdk1. Addition of cyclin B1 to fast cyclin B3-only mitosis introduces an ~60-s delay between completion of chromosome alignment and anaphase onset; this delay, which is important for segregation fidelity, is dependent on inhibitory phosphorylation of the anaphase activator Cdc20. Thus, cyclin B3 dominance, coupled to a cyclin B1-dependent delay that acts via Cdc20 phosphorylation, sets the rapid pace and ensures mitotic fidelity in the early C. elegans embryo. [ABSTRACT FROM AUTHOR]

Sensing and control of size are critical for cellular function and survival. A striking example of size sensing occurs during meiosis in the nematode Caenorhabditis elegans. C. elegans chromosomes compare the lengths of the two chromosome "arms" demarcated by the position of their single off-center crossover, and they differentially modify these arms to ensure that sister chromatid cohesion is lost specifically on the shorter arm in the first meiotic division, while the longer arm maintains cohesion until the second division. While many of the downstream steps leading to cohesion loss have been characterized, the length-sensing process itself remains poorly understood. Here, we have used cytological visualization of short and long chromosome arms, combined with quantitative microscopy, live imaging, and simulations, to investigate the principles underlying length-sensitive chromosome partitioning. By quantitatively analyzing short-arm designation patterns on fusion chromosomes carrying multiple crossovers, we develop a model in which a short-arm-determining factor originates at crossover designation sites, diffuses within the synaptonemal complex, and accumulates within crossover-bounded chromosome segments. We demonstrate experimental support for a critical assumption of this model: that crossovers act as boundaries to diffusion within the synaptonemal complex. Further, we develop a discrete simulation based on our results that recapitulates a wide variety of observed partitioning outcomes in both wild-type and previously reported mutants. Our results suggest that the concentration of a diffusible factor is used as a proxy for chromosome length, enabling the correct designation of short and long arms and proper segregation of chromosomes. [Display omitted] • CO-delimited chromosome functional arms are established in mid-meiotic prophase • Both phosphorylated and non-phosphorylated SYP-1 proteins partition to short arms • Multiple COs can act additively on domains to establish "short" or "long" identity • CO sites block diffusion along the SC, enabling potential concentration of factors The holocentric chromosomes of C. elegans lose cohesion at meiosis I in the shorter of the two domains defined by the single crossover. Rodriguez-Reza et al. provide evidence that the sensing of short versus long domains relies on comparing the concentration of crossover-derived factors accumulating within these domains as a proxy for physical length. [ABSTRACT FROM AUTHOR]

Mature neurons maintain their distinctive morphology for extended periods in adult life. Compared to developmental neurite outgrowth, axon guidance, and target selection, relatively little is known of mechanisms that maintain the morphology of mature neurons. Loss of function in C. elegans dip-2 , a member of the conserved lipid metabolic regulator Dip2 family, results in progressive overgrowth of neurites in adults. We find that dip-2 mutants display specific genetic interactions with sax-2 , the C. elegans ortholog of Drosophila Furry and mammalian FRY. Combined loss of dip-2 and sax-2 results in failure to maintain neuronal morphology and elevated release of neuronal extracellular vesicles (EVs). By screening for suppressors of dip-2(0) sax-2(0) double mutant defects, we identified gain-of-function (gf) mutations in the conserved Dopey family protein PAD-1 and its associated phospholipid flippase TAT-5/ATP9A that restore normal neuronal morphology and normal levels of EV release to dip-2(0) sax-2(0) double mutants. Neuron-specific knockdown suggests that PAD-1(gf) can act cell autonomously in neurons. PAD-1(gf) displays increased association with the plasma membrane in oocytes and inhibits EV release in multiple cell types. Our findings uncover a novel functional network of DIP-2, SAX-2, PAD-1, and TAT-5 that maintains neuronal morphology and modulates EV release. [Display omitted] • DIP-2/Dip2 and SAX-2/Fry maintain the morphology of mature neurons • dip-2 sax-2 defects are suppressed by gain of function in PAD-1 or TAT-5 • dip-2 sax-2 double mutants display increased extracellular vesicles (EVs) • PAD-1 or TAT-5 gain of function suppresses EV release Maintenance of mature neuronal morphology involves the conserved DIP-2/Dip2 lipid regulators and SAX-2/Furry scaffold proteins. Using C. elegans genetics, Park et al. identify altered function of PAD-1/Dopey in an extracellular vesicle regulatory pathway that suppresses neuronal defects due to lack of DIP-2 and SAX-2. [ABSTRACT FROM AUTHOR]

During cell division, chromosomes build kinetochores that attach to spindle microtubules. Kinetochores usually form at the centromeres, which contain CENP-A nucleosomes. The outer kinetochore, which is the core attachment site for microtubules, is composed of the KMN network (Knl1c, Mis12c, and Ndc80c complexes) and is recruited downstream of CENP-A and its partner CENP-C. In C. elegans oocytes, kinetochores have been suggested to form independently of CENP-A nucleosomes. Yet kinetochore formation requires CENP-C, which acts in parallel to the nucleoporin MEL-28ELYS. Here, we used a combination of RNAi and Degron-based depletion of CENP-A (or downstream CENP-C) to demonstrate that both proteins are in fact responsible for a portion of outer kinetochore assembly during meiosis I and are essential for accurate chromosome segregation. The remaining part requires the coordinated action of KNL-2 (ortholog of human M18BP1) and of the nucleoporin MEL-28ELYS. Accordingly, co-depletion of CENP-A (or CENP-C) and KNL-2M18BP1 (or MEL-28ELYS) prevented outer kinetochore assembly in oocytes during meiosis I. We further found that KNL-2M18BP1 and MEL-28ELYS are interdependent for kinetochore localization. Using engineered mutants, we demonstrated that KNL-2M18BP1 recruits MEL-28ELYS at meiotic kinetochores through a specific N-terminal domain, independently of its canonical CENP-A loading factor activity. Finally, we found that meiosis II outer kinetochore assembly was solely dependent on the canonical CENP-A/CENP-C pathway. Thus, like in most cells, outer kinetochore assembly in C. elegans oocytes depends on centromeric chromatin. However, during meiosis I, an additional KNL-2M18BP1 and MEL-28ELYS pathway acts in a non-redundant manner and in parallel to canonical centromeric chromatin. [Display omitted] • CENP-A/C are essential for kinetochore assembly and function in meiosis I and II • KNL-2/MEL-28 form a non-canonical kinetochore assembly pathway during meiosis I • CENP-A/C and KNL-2/MEL-28 coordinate kinetochore assembly during meiosis I • Kinetochore assembly is regulated differently between meiosis I and meiosis II Bellutti et al. demonstrate that during meiosis I in C. elegans oocytes, outer kinetochore assembly relies on both the canonical CENP-A/C centromeric pathway and a parallel non-canonical KNL-2/MEL-28 pathway. By contrast, during meiosis II, outer kinetochore assembly depends solely on the CENP-A/C pathway. [ABSTRACT FROM AUTHOR]

Neuronal communication involves small-molecule transmitters, gap junctions, and neuropeptides. While neurons often express multiple neuropeptides, our understanding of the coordination of their actions and their mutual interactions remains limited. Here, we demonstrate that two neuropeptides, NLP-10 and FLP-1, released from the same interneuron pair, AVKL/R, exert antagonistic effects on locomotion speed in Caenorhabditis elegans. NLP-10 accelerates locomotion by activating the G protein-coupled receptor NPR-35 on premotor interneurons that promote forward movement. Notably, we establish that NLP-10 is crucial for the aversive response to mechanical and noxious light stimuli. Conversely, AVK-derived FLP-1 slows down locomotion by suppressing the secretion of NLP-10 from AVK, through autocrine feedback via activation of its receptor DMSR-7 in AVK neurons. Our findings suggest that peptidergic autocrine motifs, exemplified by the interaction between NLP-10 and FLP-1, might represent a widespread mechanism in nervous systems across species. These mutual functional interactions among peptidergic co-transmitters could fine-tune brain activity. Whether and how different neuropeptides in the same neuron might be differentially regulated are not fully understood. This study in C. elegans demonstrates that the signaling of two neuropeptides, expressed in the same neuron, interacts through autocrine feedback. Their antagonistic functions fine-tune behavior in response to different stimuli. [ABSTRACT FROM AUTHOR]

Probiotics are live microorganisms that provide health benefits when administered in appropriate amounts by improving or restoring the balance of intestinal microbiota. Various functional probiotic products have been developed due to the growing interest in the health-promoting and anti-aging effects of enhancing the gut microbiome. Lactiplantibacillus plantarum species are known for their potential to extend lifespan. However, this activity is strain or isolation source specific, necessitating the identification of individual strain functionalities. This study used the C. elegans model to screen probiotics for life-extension effects and analyze their functions. The 43 lactic-acid bacteria strains isolated from fermented foods, breast milk, and human feces were subjected to longevity assays, and L. plantarum DS1800 was selected to demonstrate the most effective lifespan extension. The average lifespan of Caenorhabditis elegans fed DS1800 increased by 17.36% compared with those fed Escherichia coli OP50. Further analysis of the expression of key genes related to longevity revealed the high expression of the skinhead-1 (skn-1), antibacterial, and heat stress resistance genes via the p38 MAPK pathway. These expression patterns suggest that DS1800 extends the lifespan of C. elegans by enhancing its stress resistance and protecting it against pathogens. Additionally, DS1800 exhibited excellent intestinal adhesion, with 7.56% adhesion to HT-29 cells. Therefore, L. plantarum DS1800 is effective in extending the lifespan of C. elegans and can be used as a functional probiotic. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a neurodegenerative disorder marked by the loss of dopaminergic neurons and the formation of α-synuclein aggregates. Mitochondrial dysfunction and oxidative stress are pivotal in PD pathogenesis, with impaired mitophagy contributing to the accumulation of mitochondrial damage. Hederagenin (Hed), a natural triterpenoid, has shown potential neuroprotective effects; however, its mechanisms of action in PD models are not fully understood. We investigated the effects of Hed on 6-hydroxydopamine (6-OHDA)-induced cytotoxicity in SH-SY5Y cells by assessing cell viability, mitochondrial function, and oxidative stress markers. Mitophagy induction was evaluated using autophagy and mitophagy inhibitors and fluorescent staining techniques. Additionally, transgenic Caenorhabditis elegans (C. elegans) models of PD were used to validate the neuroprotective effects of Hed in vivo by focusing on α-synuclein aggregation, mobility, and dopaminergic neuron integrity. Hed significantly enhanced cell viability in 6-OHDA-treated SH-SY5Y cells by inhibiting cell death and reducing oxidative stress. It ameliorated mitochondrial damage, evidenced by decreased mitochondrial superoxide production, restored membrane potential, and improved mitochondrial morphology. Hed also induced mitophagy, as shown by increased autophagosome formation and reduced oxidative stress; these effects were diminished by autophagy and mitophagy inhibitors. In C. elegans models, Hed activated mitophagy and reduced α-synuclein aggregation, improved mobility, and mitigated the loss of dopaminergic neurons. RNA interference targeting the mitophagy-related genes pdr-1 and pink-1 partially reversed these benefits, underscoring the role of mitophagy in Hed's neuroprotective actions. Hed exhibits significant neuroprotective effects in both in vitro and in vivo PD models by enhancing mitophagy, reducing oxidative stress, and mitigating mitochondrial dysfunction. These findings suggest that Hed holds promise as a therapeutic agent for PD, offering new avenues for future research and potential drug development. [Display omitted] • Hederagenin (Hed) enhances mitophagy in SH-SY5Y cells and C. elegans. • Hed protects mitochondria and decreases oxidative stress via mitophagy induction. • Hed reduces α-synuclein aggregation and improves mobility in NL5901 worms. • Hed reduces the loss of neurons and improves mobility in 6-OHDA-induced BZ555 worms. • Hed exhibits neuroprotection via activating mitophagy through Pdr-1 and pink-1 genes. [ABSTRACT FROM AUTHOR]

Adhesion G protein-coupled receptors are unique molecules. They are able to transmit classical signals via G protein activation as well as mediate functions solely through their extracellular N termini, completely independently of the seven transmembrane helices domain and the C terminus. This dual mode of action is highly unusual for G protein-coupled receptors and allows for a plethora of possible cellular consequences. However, the physiological implications and molecular details of this N terminus-mediated signaling are poorly understood. Here, we show that several distinct seven transmembrane helices domain-independent/ trans functions of the adhesion G protein-coupled receptor latrophilin homolog latrophilin-1 in the nematode Caenorhabditis elegans together regulate reproduction: sperm guidance, ovulation, and germ cell apoptosis. In these contexts, the receptor elicits its functions in a noncell autonomous manner. The functions might be realized through alternative splicing of the receptor specifically generating N terminus-only variants. Thus, our findings shed light on the versatility of seven transmembrane helices domain-independent/N terminus-only/ trans functions of adhesion G protein-coupled receptor and discuss possible molecular details. [ABSTRACT FROM AUTHOR]

The synaptonemal complex (SC) is a meiotic interface that assembles between parental chromosomes and is essential for gamete formation. While the dimensions and ultrastructure of the SC are conserved across eukaryotes, its protein components are highly divergent. Recently, an unexpected component of the SC has been described in the nematode Caenorhabditis elegans : the Skp1-related proteins SKR-1/2, which are components of the Skp1, Cullin, F-box (SCF) ubiquitin ligase. Here, we find that the role of SKR-1 in the SC is conserved in Pristionchus pacificus. The P. pacificus Skp1 ortholog, Ppa-SKR-1 , colocalizes with other SC proteins throughout meiotic prophase, where it occupies the middle of the SC. Like in C. elegans , the dimerization interface of Ppa-SKR-1 is required for its SC function. A dimerization mutant, ppa-skr-1F105E , fails to assemble SC and produces almost no progeny. Interestingly, the evolutionary trajectory of SKR-1 contrasts with other SC proteins. Unlike most SC proteins, SKR-1 is highly conserved in nematodes. Our results suggest that the structural role of SKR-1 in the SC has been conserved since the common ancestor of C. elegans and P. pacificus , and that rapidly evolving SC proteins have maintained the ability to interact with SKR-1 for at least 100 million years. [ABSTRACT FROM AUTHOR]

Raf protein kinases act as Ras-GTP sensing components of the ERK signal transduction pathway in animal cells, influencing cell proliferation, differentiation, and survival. In humans, somatic and germline mutations in the genes BRAF and RAF1 are associated with malignancies and developmental disorders. Recent studies shed light on the structure of activated Raf, a heterotetramer consisting of Raf and 14-3-3 dimers, and raised the possibility that a Raf C-terminal distal tail segment (DTS) regulates activation. We investigated the role of the DTS using the Caenorhabditis elegans Raf ortholog lin-45. Truncations removing the DTS strongly enhanced lin-45 (S312A) , a weak gain-of-function allele equivalent to RAF1 mutations found in patients with Noonan Syndrome. We genetically defined three elements of the LIN-45 DTS, which we termed the active site binding sequence (ASBS), the KTP motif, and the aromatic cluster. In the context of lin-45 (S312A) , the mutation of each of these elements enhanced activity. We used AlphaFold to predict DTS protein interactions for LIN-45 , fly Raf, and human BRAF within the activated heterotetramer complex. We propose the following distinct functions for the LIN-45 DTS elements: (1) the ASBS binds the kinase active site as an inhibitor; (2) phosphorylation of the KTP motif modulates the DTS–kinase domain interaction; and (3) the aromatic cluster anchors the DTS in an inhibitory conformation. Human RASopathy-associated variants in BRAF affect residues of the DTS, consistent with these predictions. This work establishes that the Raf/ LIN-45 DTS negatively regulates signaling in C. elegans and provides a model for its function in other Raf proteins. [ABSTRACT FROM AUTHOR]

Life history is defined by traits that reflect key components of fitness, especially those relating to reproduction and survival. Research in life history seeks to unravel the relationships among these traits and understand how life history strategies evolve to maximize fitness. As such, life history research integrates the study of the genetic and developmental mechanisms underlying trait determination with the evolutionary and ecological context of Darwinian fitness. As a leading model organism for molecular and developmental genetics, Caenorhabditis elegans is unmatched in the characterization of life history-related processes, including developmental timing and plasticity, reproductive behaviors, sex determination, stress tolerance, and aging. Building on recent studies of natural populations and ecology, the combination of C. elegans ' historical research strengths with new insights into trait variation now positions it as a uniquely valuable model for life history research. In this review, we summarize the contributions of C. elegans and related species to life history and its evolution. We begin by reviewing the key characteristics of C. elegans life history, with an emphasis on its distinctive reproductive strategies and notable life cycle plasticity. Next, we explore intraspecific variation in life history traits and its underlying genetic architecture. Finally, we provide an overview of how C. elegans has guided research on major life history transitions both within the genus Caenorhabditis and across the broader phylum Nematoda. While C. elegans is relatively new to life history research, significant progress has been made by leveraging its distinctive biological traits, establishing it as a highly cross-disciplinary system for life history studies. [ABSTRACT FROM AUTHOR]

Germ cell development and gamete production in animals require small RNA pathways. While studies indicate that microRNAs (miRNAs) are necessary for normal sperm production and function, the specific roles for individual miRNAs are largely unknown. Here, we use small RNA sequencing (RNA-seq) of dissected gonads and functional analysis of new loss-of-function alleles to identify functions for miRNAs in the control of fecundity and sperm production in Caenorhabditis elegans males and hermaphrodites. We describe a set of 29 male gonad-enriched miRNAs and identify a set of individual miRNAs (mir-58.1 and mir-235) and a miRNA cluster (mir-4807 -4810.1) that are required for optimal sperm production at 20°C and a set of miRNAs (mir-49 , mir-57 , mir-83 , mir-261 , and mir-357 /358) that are required for sperm production at 25°C. We observed defects in meiotic progression in mutants missing mir-58.1 , mir-83 , mir-235 , and mir-4807 -4810.1 , which may contribute to the observed defects in sperm production. Further, analysis of multiple mutants of these miRNAs suggested genetic interactions between these miRNAs. This study provides insights on the regulatory roles of miRNAs that promote optimal sperm production and fecundity in males and hermaphrodites. [ABSTRACT FROM AUTHOR]

Neuropeptides are abundant signaling molecules that control neuronal activity and behavior in all animals. Owing in part to its well-defined and compact nervous system, Caenorhabditis elegans has been one of the primary model organisms used to investigate how neuropeptide signaling networks are organized and how these neurochemicals regulate behavior. We here review recent work that has expanded our understanding of the neuropeptidergic signaling network in C. elegans by mapping the evolutionary conservation, the molecular expression, the receptor–ligand interactions, and the system-wide organization of neuropeptide pathways in the C. elegans nervous system. We also describe general insights into neuropeptidergic circuit motifs and the spatiotemporal range of peptidergic transmission that have emerged from in vivo studies on neuropeptide signaling. With efforts ongoing to chart peptide signaling networks in other organisms, the C. elegans neuropeptidergic connectome can serve as a prototype to further understand the organization and the signaling dynamics of these networks at organismal level. [ABSTRACT FROM AUTHOR]

During challenge of Caenorhabditis elegans with human bacterial pathogens such as Pseudomonas aeruginosa and Enterococcus faecalis , the elicited host response can be damaging if not properly controlled. The activation of Nrf (nuclear factor erythroid-related factor)/CNC (Cap-n-collar) transcriptional regulators modulates the response by upregulating genes that neutralize damaging molecules and promote repair processes. Activation of the C. elegans Nrf ortholog, SKN-1 , is tightly controlled by a myriad of regulatory mechanisms, but a central feature is an activating phosphorylation accomplished by the p38 mitogen-activated kinase (MAPK) cascade. In this work, loss of CDC-48, an AAA+ ATPase, was observed to severely compromise SKN-1 activation on pathogen and we sought to understand the mechanism. CDC-48 is part of the endoplasmic reticulum (ER)-associated degradation (ERAD) complex where it functions as a remodeling chaperone enabling the translocation of proteins from the ER to the cytoplasm for degradation by the proteosome. Interestingly, one of the proteins retrotranslocated by ERAD, a process necessary for its activation, is SKN-1A, the ER isoform of SKN-1. However, we discovered that SKN-1A is not activated by pathogen exposure in marked contrast to the cytoplasmic-associated isoform SKN-1C. Rather, loss of CDC-48 blocks the antioxidant response normally orchestrated by SKN-1C by strongly inducing the unfolded protein response (UPRER). The data are consistent with the model of these 2 pathways being mutually inhibitory and support the emerging paradigm in the field of coordinated cooperation between different stress responses. [ABSTRACT FROM AUTHOR]

The extraction process of crude polysaccharides from Agrocybe aegerita was optimized, and the antioxidant and anti-aging effects of the crude polysaccharides were evaluated. The optimal extraction parameters for the polysaccharide were identified using the response surface methodology. The DPPH, hydroxy radical, and superoxide anion radical scavenging capacities were evaluated to determine the antioxidant properties of the AAPs. The effects of the AAPs on the lifespan, head-swing frequency, swallowing frequency, body-bending frequency, and stress resistance of Caenorhabditis elegans were determined. The optimal extraction conditions included a solid-to-liquid ratio that resulted in an extraction solution concentration of 0.034 g/mL, an extraction temperature of 92.64 °C, and an extraction time of 2.82 h. Under these conditions, the yield of the AAPs was 11.325% ± 0.996%. The IC50 of the AAPs for superoxide anion radical scavenging was 4.693 mg/mL. The AAPs reached their maximum activity at concentrations of about 2 mg/mL for DPPH and 5 mg/mL for the hydroxyl radical. The AAPs could prolong the lifespan and improve locomotion and the stress resistance of C. elegans. Our findings illustrate the potential of AAPs as an anti-aging and antioxidant agent, highlighting the use of this natural compound in the fields of food and pharmacology. [ABSTRACT FROM AUTHOR]

In previous research, we created a C. elegans model with homozygous mutations in calreticulin similar to those found in patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF), two myeloproliferative neoplasms (MPNs). This model, lacking JAK orthologs, enabled us to examine the transcriptomic effects caused by mutant calreticulin without the influence of JAK/STAT activation, the primary pathogenic mechanism associated with calreticulin mutations known to date. Most of the gene expression changes observed seemed to be due to a partial loss of protein function, with the alteration of the extracellular matrix being particularly notable. In this study, our aim was to determine whether this model exhibited any phenotype related to these transcriptomic alterations. The results demonstrate that these strains exhibit multiple phenotypes related to the alteration of the extracellular matrix, fat levels, and fertility, which could be a possible consequence of a partial loss of calreticulin function. These phenotypes resemble some of the clinical and molecular characteristics described in patients with MPNs, but they had never before been linked to a loss of protein function in humans. Thus, these results collectively suggest that CALR mutations could have significant effects on MPNs due to loss of protein function. Delving deeper into these effects to develop innovative therapies for these patients offers considerable potential and interest, given that targeted therapies for these patients have not yielded very promising results so far. [ABSTRACT FROM AUTHOR]

Through this study, the synergistic behavior of small-molecular-weight, amphiphilic surfactant molecules and the triblock copolymer Pluronic 188 was extensively evaluated based on their ability to formulate nanocarriers with novel properties for the delivery of class II and IV (biopharmaceutical classification system) chemotherapeutic compounds. The combination of four different surfactants at multiple weight ratios and twelve initially formulated nanosystems resulted in four hybrid delivery platforms, which were further studied in terms of multiple physicochemical characteristics, as well as their stability in protein-rich media (fetal bovine serum/phosphate-buffer saline). Finally, we obtained a single final nanoformulation that exhibited a high loading capacity (%EE ≥ 75%) and a sustained drug release profile under physiological conditions (model drug methotrexate), without altering the original physicochemical characteristics of the carrier. With a mean hydrodynamic radius (Rh) of less than 70 nm, a polydispersity index of 0.219, and no protein complexation, the system is a suitable candidate for in vivo, intravenous, and/or intramuscular administration. The cytotoxicity and genotoxicity of both loaded and unloaded carriers were evaluated through the examination of the upregulation or downregulation of apoptosis-related pathways. Multiple conventional 2D and 3D spheroidal conformations were used for these assessments, including HEK293, HCT-116, and MCF-7 cell lines, the results of which stressed the safety and biocompatibility of the empty nanocarrier. Additionally, experiments on Caenorhabditis elegans were conducted to evaluate the system's in vivo toxicity, focusing on developmental stages, egg-laying behavior, and locomotion. Nanosystems studied in terms of chemotherapeutic encapsulation have mostly focused on the physiochemical aspect of the development of such novel delivery platforms, with only few exceptions proceeding step-by-step from cellular 2D to 3D to in vivo experimentation. The present study offers a holistic view of the behavior of such a novel system, advancing our understanding of the capabilities of polymeric/surfactant-based nanodelivery platforms. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION The black goji berry (Lycium ruthenicum Murr.) is known for its abundance of high‐quality natural antioxidants, particularly anthocyanins. Black goji berry anthocyanins (BGA) are receiving increasing attention because of their high safety and beneficial biological activities. Studies have shown that oxidative stress is a key factor affecting aging, whereas antioxidants are critical preventive and delaying strategies.In the present study, we investigated the potential anti‐aging effects and mechanism of BGA using the Caenorhabditis elegans model. We found that BGA prolonged the mean lifespan of nematodes and improve their healthspan, including locomotion, pharyngeal pumping rate and stress resistance. Subsequently, we observed a significant decrease in reactive oxygen species and malondialdehyde levels in nematodes after administering BGA. Moreover, BGA enhanced the activities of the antioxidant enzymes superoxide dismutase and catalase, and elevated the glutathione disulfide/glutathione ratio. We confirmed that BGA exerted excellent antioxidative stress activity in nematodes, which may contribute substantially to its anti‐aging effects. The health benefits of BGA in C. elegans might be closely related to petunidin‐3‐O‐glucoside, the most abundant anthocyanin in BGA. Further mechanistic investigation revealed that the JNK‐1 and DAF‐16/FOXO pathways, rather than the calorie restriction pathway, were responsible for the antioxidant stress and life‐prolonging effects of BGA in nematodes.Our research provides a theoretical foundation for studying the anti‐aging effect of BGA and a basis for developing black goji berry and its anthocyanins as functional foods with anti‐aging and antioxidative stress benefits. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The maintenance of germ cells is critical for the prosperity of offspring. The amount of food consumption is known to be closely related to reproduction, i.e. the number of eggs decreases under calorie-restricted conditions in various organisms. Previous studies in Caenorhabditis elegans have reported that calorie restriction reduces the number of eggs and the reduction can be rescued by methionine. However, the effect of methionine on the reproductive process has not been fully understood. In this study, to assess the gonadal function of methionine metabolism, we firstly demonstrated that a depletion in dietary methionine resulted in reduced levels of S -adenosyl- l -methionine (SAM) and S -adenosyl homocysteine in wild-type N2, but not in glp-1 mutants, which possess only a few germ cells. Second, we found no recovery in egg numbers upon methionine administration in SAM synthase (sams) -1 mutants. Furthermore, a reduced number of proliferative zone nuclei exhibited in the sams-1 mutants was not rescued via methionine. Thus, our results have shown that dietary methionine is required for the normal establishment of both the germline progenitor pool and fecundity, mediated by sams-1. [ABSTRACT FROM AUTHOR]

Aging is a complex biological process characterized by gradual and irreversible functional deterioration, strongly associated with oxidative stress. Pentagalloyl glucose (PGG) has attracted increasing attention due to its potent antioxidant and anti-stress properties. This study investigated the potential of PGG to mitigate the aging process under stress in RAW 264.7 cells and Caenorhabditis elegans models. The expression of vital genes associated with stress was also measured to explain the action mechanism of PGG in C. elegans. The findings showed that PGG supplementation not only significantly enhanced the stress tolerance of RAW 264.7 cells, but also prolonged lifespan and reduced the ROS and lipofuscin accumulation in C. elegans induced by stress. Meanwhile, the improvement effect of PGG on delaying aging development was also manifested in the protection of mitochondrial function and neuronal integrity. Moreover, daf-16 nuclear translocation and sod-3 expression were significantly enhanced by PGG to delay the aging process. Mechanistically, PGG might alleviate aging by improving daf-16 , sod-3 , ctl-1 , and gst-4 levels in the DAF-16/FOXO pathway and upregulating skn-1 and gst-4 expression in the SKN-1/Nrf2 pathway. Our study provided novel insights into the role of PGG in combating stress-induced aging. [Display omitted] • Pentagalloyl glucose (PGG) enhanced the viability and antioxidant capacity in monocyte/macrophage-like cell lineage RAW 264.7 cells. • PGG improved the reactive oxygen species generation (ROS), lifespan, lipofuscin in C. elegans. • PGG alleviated the mitochondrial dysfunction and neuronal degeneration. • PGG regulated the expression of daf-16 sod-3 , clt-1 skn-1 and gst-4 to delay aging. [ABSTRACT FROM AUTHOR]

This research explores the remarkable impact of fermented cereals such as sorghum, maize, and wheat with Pediococcus acidilactici WS07, a strain isolated from Ethiopia's traditional borde beverage. The fermented cereal extracts were thoroughly evaluated for antioxidant activity, inhibition of pancreatic lipase and α-glucosidase, metabolite identification through UHPLC-Q-TOF-MS/MS, and in vivo efficacy using the C. elegans model. The results revealed significant enhancements in the bioactive compounds of fermented cereals, demonstrating promising directions for obesity prevention strategies. Notably, the fermented sorghum extracts improved lipase (88.23 %) and α-glucosidase (85.62 %) inhibitory activities compared to its unfermented counterparts. The antioxidant properties of all fermented samples were confirmed through improved DPPH (67.77–71.86 %) and ABTS (59.91–65.49 %) scavenging activities. Fermentation also led to a notable increase in polyphenols and flavonoids, with detailed metabolite analysis revealing a dynamic shift in the composition of these bioactive compounds. Additionally, C. elegans indicates that fermented extracts extend lifespan, reduce lipid accumulation, and lower triglycerides, highlighting their potential as functional foods for health enhancement and obesity management. This study not only underscores the efficacy of P. acidilactici WS07 fermentation in transforming cereals into nutrient-rich functional foods but also provides insight into how microbial fermentation can unlock the health-promoting potential of traditional diets. [Display omitted] • Fermented sorghum extracts inhibited lipase (88.23 %) and α-glucosidase (85.62 %). • Fermented extracts showed superior antioxidant properties vs. unfermented. • Fermented sorghum and sorghum-maize extended lifespan, reduced lipids in C. elegans. • P. acidilactici WS07-fermented sorghum can be used to develop anti-obesity foods. [ABSTRACT FROM AUTHOR]

Computational image analysis combined with label‐free imaging has helped maintain its relevance for cell biology, despite the rapid technical improvements in fluorescence microscopy with the molecular specificity of tags. Here, we discuss some computational tools developed in our lab and their application to quantify cell shape, intracellular organelle movement and bead transport in vitro, using differential interference contrast (DIC) microscopy data as inputs. The focus of these methods is image filtering to enhance image gradients, and combining them with segmentation and single particle tracking (SPT). We demonstrate the application of these methods to Escherichia coli cell length estimation and tracking of densely packed lipid granules in Caenorhabditis elegans one‐celled embryos, diffusing beads in solutions of different viscosities and kinesin‐driven transport on microtubules. These approaches demonstrate how improvements to low‐level image analysis methods can help obtain insights through quantitative cellular and subcellular microscopy. [ABSTRACT FROM AUTHOR]

Sediment is the ultimate sink of environmental pollutants. A total of 128 surface sediment samples were collected from 8 rivers and 3 reservoirs in Maoming City, Guangdong Province. This study assessed the content and distribution of brominated flame retardants in sediments. The acute toxicity effects of tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDs) in sediments were evaluated using Caenorhabditis elegans as model organisms. The concentration of TBBPA in sediments ranged from not detected (ND) to 12.59 µg/kg and was mainly distributed in the central area, which was affected by the emission of TBBPA from residential and factory. The concentration of HBCDs ranged from ND to 6.31 µg/kg, and the diastereoisomer distribution was consistent, showing a trend close to the South China Sea. The composition pattern of HBCDs in the surface sediments from rivers were 41.73%–62.33%, 7.89%–25.54%, and 18.76%–40.65% for α-, β-, and γ-HBCD, respectively, and in the sediments from reservoirs were 26.15%–45.52%, 7.44%–19.23%, and 47.04%–61.89% for α-, β-, and γ-HBCD, respectively. When the sum of concentrations of TBBPA and HBCD in sediments were above high levels, reactive oxygen species in nematodes significantly increased, resulting in an oxidative stress response. Intestinal permeability was also enhanced, causing intestinal damage. In addition, in terms of this study, TBBPA had a greater impact on biotoxicity compared to HBCDs, and more attention should be paid to the toxic effects of the river ecosystem organisms in Maoming City, Guangdong Province. This study can complement the pollution database in the study area and provide basic data for pollution control. [Display omitted] [ABSTRACT FROM AUTHOR]

The transmission of acetylcholine (ACh) is critically important for memory, learning, and behaviour. The most promising approaches for the treatment of cholinergic dysfunction involve the enhancement of ACh via nootropic phytomolecules. In the same line, the present study identifies the active molecule Bakuchiol derived from Psoralea corylifolia. Bakuchiol demonstrated significant elevation of ACh transmission, reduction of reactive oxygen species (ROS) levels, and extension of lifespan. Further investigation indicated that modulation of mRNA expression of genes encoding choline transporter, choline acetyltransferase, and acetylcholine transporter as possible effectors of amassed neural transmission. Moreover, Bakuchiol showed efficacy in reducing amyloid β and lipid levels, possibly through the upregulation of heat shock transcription factor 1 (hsf-1) and autophagy (lgg-1) genes. Overall, our findings establish the efficacy of Bakuchiol in modulating cholinergic dysfunction. [ABSTRACT FROM AUTHOR]