• Molecules and Cells
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• v.39 no.2
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• pp.163-168
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• 2016

Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

• Molecules and Cells
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• v.38 no.1
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• pp.51-57
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• 2015

The Caenorhabditis elegans peroxidasins, PXN-1 and PXN-2, are extracellular peroxidases; pxn-2 is involved in muscle-epidermal attachment during embryonic morphogenesis and in specific axon guidance. Here we investigate potential roles of the other homologue of peroxidasin, pxn-1, in C. elegans. A pxn-1 deletion mutant showed high lethality under heat-stress conditions. Using a transcriptional GFP reporter, pxn-1 expression was observed in various tissues including neurons, muscles, and hypodermis. A translational fusion showed that PXN-1::GFP was secreted and localized in extracellular matrix, particularly along body wall muscles and pharyngeal muscles. Various neuronal developmental defects were observed in pxn-1 mutants and in pxn-1 over-expressing animals, including handedness, branching, breakage, tangling, and defasciculation. These results suggest that pxn-1, like other peroxidasins, plays an important role throughout development.

• Molecules and Cells
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• v.37 no.1
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• pp.51-57
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• 2014

NOG1 is a nucleolar GTPase that is critical for 60S ribosome biogenesis. Recently, NOG1 was identified as one of the downstream regulators of target of rapamycin (TOR) in yeast. It is reported that TOR is involved in regulating lifespan and fat storage in Caenorhabditis elegans. Here, we show that the nog1 ortholog (T07A9.9: nog-1) in C. elegans regulates growth, development, lifespan, and fat metabolism. A green fluorescence protein (GFP) promoter assay revealed ubiquitous expression of C. elegans nog-1 from the early embryonic to the adult stage. Furthermore, the GFP-tagged NOG-1 protein is localized to the nucleus, whereas the aberrant NOG-1 protein is concentrated in the nucleolus. Functional studies of NOG-1 in C. elegans further revealed that nog-1 knockdown resulted in smaller broodsize, slower growth, increased life span, and more fat storage. Moreover, nog-1 over-expression resulted in decreased life span. Taken together, our data suggest that nog-1 in C. elegans may be an important player in regulating life span and fat storage via the insulin/IGF pathway.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.166-182
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• 2022

Deer antler velvet is widely used in traditional medicine for its anti-aging, antioxidant, and immunity-enhancing effects. However, few studies have reported on the discovery of probiotic strains for deer antler fermentation to increase functional ingredient absorption. This study evaluated the ability of probiotic lactic acid bacteria to enhance the concentrations of bioactive molecules (e.g., sialic acid and gamma-aminobutyric acid [GABA]) in extracts of deer antler velvet. Seventeen strains of Lactobacillus spp. that were isolated from kimchi and infant feces, including L. sakei, L. rhamnosus, L. brevis, and L. plantarum, and those that improved the life span of Caenorhabditis elegans were selected for evaluation. Of the 17 strains, 2 (L. rhamnosus LFR20-004 and L. sakei LFR20-007) were selected based on data showing that these strains increased both the sialic acid and GABA contents of deer antler extract after fermentation for 2 d and significantly improved the life span of C. elegans. Co-fermentation with both strains further increased the concentrations of sialic acid, GABA, and metabolites such as short-chain fatty acids and amino acids. We evaluated the biological effects of the fermented antler velvet (FAV) on the antibacterial immune response in C. elegans by assessing worm survival after pathogen infection. The survival of the C. elegans conditioned with FAV for 24h was significantly higher compared with that of the control worm group fed only normal feed (non-pathogenic E. coli OP50) exposed to E. coli O157:H7, Salmonella typhi, and Listeria monocytogenes. To evaluate the protective effects of FAV on immune response, cyclophosphamide (Cy), an immune-suppressing agent was treated to in vitro and in vivo. We found that FAV significantly restored viability of mice splenocytes and immune promoting-related cytokines (interleukin [IL]-6, IL-10, inducible nitric oxide synthase [iNOS], interferon [IFN]-γ, and tumor necrosis factor [TNF]-α) were activated compared to non-fermented deer antlers. This finding indicated the protective effect of FAV against Cy-induced cell death and immunosuppressed mice. Taken together, our study suggests that immune-promoting antler velvet can be produced through fermentation using L. rhamnosus LFR20-004 and L. sakei LFR20-007.

• BMB Reports
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• v.37 no.1
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• pp.107-113
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• 2004

Since the completion of the genome project of the nematode C. elegans in 1998, functional genomic approaches have been applied to elucidate the gene and protein networks in this model organism. The recent completion of the whole genome of C. briggsae, a close sister species of C. elegans, now makes it possible to employ the comparative genomic approaches for identifying regulatory mechanisms that are conserved in these species and to make more precise annotation of the predicted genes. RNA interference (RNAi) screenings in C. elegans have been performed to screen the whole genome for the genes whose mutations give rise to specific phenotypes of interest. RNAi screens can also be used to identify genes that act genetically together with a gene of interest. Microarray experiments have been very useful in identifying genes that exhibit co-regulated expression profiles in given genetic or environmental conditions. Proteomic approaches also can be applied to the nematode, just as in other species whose genomes are known. With all these functional genomic tools, genetics will still remain an important tool for gene function studies in the post genome era. New breakthroughs in C. elegans biology, such as establishing a feasible gene knockout method, immortalized cell lines, or identifying viruses that can be used as vectors for introducing exogenous gene constructs into the worms, will augment the usage of this small organism for genome-wide biology.

• The Korean Journal of Mycology
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• v.40 no.1
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• pp.54-59
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• 2012

This study investigates the effect of ${\beta}$-glucans on the growth of Caenorhabditis elegans. Comparison was made among lipopolysaccharide (LPS) and ${\beta}$-glucans extracted from Phellinus baumii, in the presence of peptidoglycans which is available as the major carbon source from OP50, a non-pathogenic strain of Escherichia coli. When the three sources of carbohydrate were added singularly or in mixture to the culture media, a significant level of variation was observed with respect to fecundity. Addition of ${\beta}$-glucans appeared to increase the fecundity. When ${\beta}$-glucans was reinforced in the culture media, the fecundity increased at least 20 percent compared to the OP50-only media which exclusively contains peptidoglycans. In terms of life span, C. elegans showed a modest reduction when treated especially with ${\beta}$-glucans. C. elegans accumulated less fat in the ${\beta}$-glucans containing media different from the OP50 media. Based on the Sudan black staining, fat deposition significantly decreased corresponding to the ${\beta}$-glucans content in the media. On LPS-supplemented media, no difference was observed in fat deposition compared to the normal OP50 media. At the level of motility, ${\beta}$-glucans-treated worms moved more distance as well as LPS-treated worm. They also showed a comparable degree of motility under similar treatment with each source of carbohydrate. In conclusion, LPS and ${\beta}$-glucans, extracted from P. baumii, may not entirely replace the food required for C. elegans; however, it might be utilized as valuable alternative food source which C. elegans use as forms of carbohydrates in stead of peptidoglycan of OP50.

• Proceedings of the IEEK Conference
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• summer
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• pp.417-420
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• 2004

Caenorhabditis (C) elegans is often used in genetic analysis in neuroscience because its simple organism; an adult hermaphrodite contains only 302 neuron. So the worm is often used to study of cancer, alzheimer disease, aging, etc. To analysis mutant type of the worm, an experienced observer was able to subjectively before, but requirements for objective analysis are now increasing. For this reason, we use automated tracking systems to extract global movement coordinate of the worm. In this paper, we extract features, which are related on reversal and movement of the worm. Using these features, we quantitatively analysis 6 type mutant by movement and reversal characteristic.

• Molecules and Cells
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• v.20 no.2
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• pp.228-234
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• 2005

Caenorhabditis elegans him-6 mutants, which show a high incidence of males and partial embryonic lethality, are defective in the orthologue of human Bloom's syndrome protein (BLM). When strain him-6(e1104) containing a missense him-6 mutation was irradiated with ${\gamma}$-rays during germ cell development or embryogenesis, embryonic lethality was higher than in the wild type, suggesting a critical function of the wild type gene in mitotic and pachytene stage germ cells as well as in early embryos. Even in the absence of ${\gamma}$-irradiation, apoptosis was elevated in the germ cells of the him-6 strain and this increase was dependent on a functional p53 homologue (CEP-1), suggesting that spontaneous DNA damage accumulates due to him-6 deficiency. However, induction of germline apoptosis by ionizing radiation was not significantly affected by the deficiency, indicating that HIM-6 has no role in the induction of apoptosis by exogenous DNA damage. We conclude that the C. elegans BLM orthologue is involved in DNA repair in promeiotic cells undergoing homologous recombination, as well as in actively dividing germline and somatic cells.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.192.1-192
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• 2001

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.193.2-193
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• 2001

No Abstract, See Full Text