Morrison GE et al. (1999) Behav Neurosci "Olfactory associative learning in Caenorhabditis elegans is impaired in lrn-1 and lrn-2 mutants."

Runciman S, van der Kooy D, Wen JYM, Morrison GE

[Behav Neurosci, 1999]

The C. elegans mutants, lrn-1 and lrn-2, are impaired in associative learning using conditioned taste cues. Both mutants are defective in associative learning about appetitive and aversive events, indicating that lrn-1 and lrn-2 exert effects across motivational boundaries. In a new olfactory associative learning paradigm, in which wild type worms learn to avoid a previously attractive diacetyl odor after it has been paired with an aversive acetic acid solution, lrn-1 and lrn-2 are impaired. Although defective in associative learning using a conditioned olfactory cue, nonassociative learning (habituation and dishabituation) using this same olfactory cue is unaffected. The discovery that lrn-1 and lrn-2 are defective in associative learning with both taste and olfactory cues may suggest that associative learning in different sensory modalities converges on a common genetic pathway in C. elegans that is subserved by lrn-1 and lrn-2.

Morrison GE et al. (2001) Behav Neurosci "A mutation in the AMPA-type glutamate receptor, glr-1, blocks olfactory associative and nonassociative learning in Caenorhabditis elegans."

van der Kooy D, Morrison GE

[Behav Neurosci, 2001]

The alpha -amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)-type ionotropic glutamate receptor mediates fast excitatory neurotransmission in the vertebrate brain and is important for synaptic plasticity and the initial induction of long-term potentiation (LTP). This study found that the putative Caenorhabditis elegans AMPA receptor gene. glr-1. plays a significant role in experience-dependent behavior in C. elegans. glr-1 mutants are deficient in an olfactory associative learning task, in which diacetyl (DA) is paired with acetic acid solution. glr-1 mutant nematodes are also impaired in nonassociative learning (habituation) with the same DA stimulus. The C elegans learning mutants, lrn-1 and lrn-2. are impaired in chemosensory associative learning yet have no deficits in habituation. The results suggest that although associative and nonassociative learning can be genetically dissociated (lrn-1 and lrn-2), they also share some common molecular processes, including glr-1-mediated neurotransmission.

Morrison GE et al. (1997) Behav Neurosci "Cold shock before associative conditioning blocks memory retrieval, but cold shock after conditioning blocks memory retention in Caenorhabditis elegans."

Morrison GE, van der Kooy D

[Behav Neurosci, 1997]

The effects of cooling on associative learning and memory processes in Caenorhabditis elegans were investigated by giving the worms cold shock at various times before or after conditioning. A pretraining cold shock in the 30 min immediately before conditioning and a posttraining cold shock in the 30 min immediately after conditioning both disrupted learning and memory processes tested a short time after conditioning. However, if tested 3 hr after conditioning, worms given a pretraining cold shock demonstrated learned preferences, whereas worms given a posttraining cold shock still had memory deficits. These results suggest that the effects of cold shock on associative learning and memory can be dissociated into effects on memory retrieval and memory retention.

Xu T et al. (2022) Food Funct "Longevity-promoting properties of ginger extract in Caenorhabditis elegans via the insulin/IGF-1 signaling pathway."

Tao M, Pan S, Xu T, Wu T, Li R, Xu X

[Food Funct, 2022]

Ginger is a traditional medicinal and edible plant with multiple health-promoting properties. Nevertheless, the effects and potential mechanism of ginger on antiaging remain unknown. The aim of this study was to comprehend the antiaging effects and potential mechanism of ginger in Caenorhabditis elegans (C. elegans). The current findings showed that the lifespan of C. elegans was prolonged by 23.16% with the supplementation of 60 μg mL-1 ginger extract (GE), and the extension of lifespan was mainly attributed to the major bioactive compounds in GE, 6-, 8-, 10-gingerol and 6-, 8-, 10-shogaol. Subsequently, GE promoted healthy aging by improving nematode movement and attenuating lipofuscin accumulation, and enhanced stress tolerance by up-regulating the expression of stress-related genes and activating DAF-16 and SKN-1. Moreover, lifespan assays of relative mutants revealed that GE mediated extension of lifespan via the insulin/IGF-1 signaling (IIS) pathway. In summary, GE endowed nematodes (C. elegans) with longevity and stress resistance in an IIS pathway dependent manner.

Aranaz P et al. (2021) Nutrients "Grifola frondosa (Maitake) Extract Reduces Fat Accumulation and Improves Health Span in C. elegans through the DAF-16/FOXO and SKN-1/NRF2 Signalling Pathways."

Vettorazzi A, Fabra MJ, Aranaz P, Pena A, Castellari M, Parlade J, Gonzalez-Navarro CJ, Pera J, Martinez-Abad A, Milagro FI, Lopez-Rubio A

[Nutrients, 2021]

In recent years, food ingredients rich in bioactive compounds have emerged as candidates to prevent excess adiposity and other metabolic complications characteristic of obesity, such as low-grade inflammation and oxidative status. Among them, fungi have gained popularity for their high polysaccharide content and other bioactive components with beneficial activities. Here, we use the <i>C. elegans</i> model to investigate the potential activities of a <i>Grifola frondosa</i> extract (GE), together with the underlying mechanisms of action. Our study revealed that GE represents an important source of polysaccharides and phenolic compounds with in vitro antioxidant activity. Treatment with our GE extract, which was found to be nongenotoxic through a <i>SOS/umu</i> test, significantly reduced the fat content of <i>C. elegans</i>, decreased the production of intracellular ROS and aging-lipofuscin pigment, and increased the lifespan of nematodes. Gene expression and mutant analyses demonstrated that the in vivo anti-obesity and antioxidant activities of GE were mediated through the <i>daf-2/daf-16</i> and <i>skn-1/nrf-2</i> signalling pathways, respectively. Taken together, our results suggest that our GE extract could be considered a potential functional ingredient for the prevention of obesity-related disturbances.

Huang CH et al. (2015) J Nutr Biochem "Analysis of lifespan-promoting effect of garlic extract by an integrated metabolo-proteomics approach."

Hsu FY, Wu YH, Liang SS, Kuo CJ, Hsu AL, Chiou SH, Huang CH, Zhong L, Tseng MY

[J Nutr Biochem, 2015]

The beneficial effects of garlic (Allium sativum) consumption in treating human diseases have been reported worldwide over a long period of human history. The strong antioxidant effect of garlic extract (GE) has also recently been claimed to prevent cancer, thrombus formation, cardiovascular disease and some age-related maladies. Using Caenorhabditis elegans as a model organism, aqueous GE was herein shown to increase the expression of longevity-related FOXO transcription factor daf-16 and extend lifespan by 20%. By employing microarray and proteomics analysis on C. elegans treated with aqueous GE, we have systematically mapped 229 genes and 46 proteins with differential expression profiles, which included many metabolic enzymes and yolky egg vitellogenins. To investigate the garlic components functionally involved in longevity, an integrated metabolo-proteomics approach was employed to identify metabolites and protein components associated with treatment of aqueous GE. Among potential lifespan-promoting substances, mannose-binding lectin and N-acetylcysteine were found to increase daf-16 expression. Our study points to the fact that the lifespan-promoting effect of aqueous GE may entail the DAF-16-mediated signaling pathway. The result also highlights the utility of metabolo-proteomics for unraveling the complexity and intricacy involved in the metabolism of natural products in vivo.

Morita S et al. (2001) Physica A "Geometrical structure of the neuronal network of Caenorhabditis elegans."

Funabashi Y, Morita S, Oka K, Oshio K, Osana Y, Kawamura K

[Physica A, 2001]

The neuronal network of the soil nematode Caenorhabditis elegans (C. elegans), which is a good prototype for biological studies, is investigated. Here, the neuronal network is simplified as a graph. We use three indicators to characterize the graph; vertex degree, generalized eccentricity (GE), and complete subgraphs. The graph has the central part and the strong clustering structure. We present a simple model, which shows that the neuronal network has a high-dimensional geometrical structure.

Pooranachithra M et al. (2021) J Proteomics "Proteomic analysis of Caenorhabditis elegans wound model reveals novel molecular players involved in repair."

Pooranachithra M, Bhaskar JP, Balamurugan K, Kumar CS, Venkateswaran K, Ravichandiran V

[J Proteomics, 2021]

Wound repair is a multistep process which involves coordination of multiple molecular players from different cell types and pathways. Though the cellular processes that are taking place in order to repair damage is already known, molecular players involved in crucial pathways are still scarce. In this regard, the present study intends to uncover crucial players that are involved in the central repair events through proteomics approach which included 2-D GE and LC-MS/MS using Caenorhabditis elegans wound model. Initial gel-based 2-D GE and following protein-protein interaction (PPI) network analyses revealed active role of calcium signaling, acetylcholine transport and serotonergic neurotransmitter pathways. Further, gel-free LC-MS/MS and following PPI network analyses revealed the incidence of actin nucleation at the initial hours immediately after injury. Further by visualizing the PPI network and the interacting players, pink-1, a mitochondrial Serine/threonine-protein kinase which is known to regulate mitochondrial dynamics, was found to be the central player in facilitating the mitochondrial fission and its role was further verified using qPCR analysis and pink-1 transgenic worms. Overall, the study delivers new insights from crucial regulatory pathways and central players involved in wound repair using high throughput proteomic approaches and the mass spectrometry Data (PXD024629/px-submission #487081) are available via ProteomeXchange. SIGNIFICANCE.

Mawuenyega KG et al. (2003) J Proteome Res "Large-scale identification of Caenorhabditis elegans proteins by multidimensional liquid chromatography-tandem mass spectrometry."

Shinkawa T, Mawuenyega KG, Saito H, Yamauchi Y, Isobe T, Taoka M, Kaji H, Takahashi N

[J Proteome Res, 2003]

A proteome of a model organism, Caenorhabditis elegans, was analyzed by an integrated liquid chromatography (LC)-based protein identification system, which was constructed by microscale two-dimensional liquid chromatography (2DLC) coupled with electrospray ionization (ESI) tandem mass spectrometry (MS/MS) on a high-resolution hybrid mass spectrometer with an automated data analysis system. Soluble and insoluble protein fractions were prepared from a mixed growth phase culture of the worm C. elegans, digested with trypsin, and fractionated separately on the 2DLC system. The separated peptides were directly analyzed by on-line ESI-MS/MS in a data-dependent mode, and the resultant spectral data were automatically processed to search a genome sequence database, wormpep 66, for protein identification. The total number of proteins of the composite proteome identified in this method was 1616, including 110 secreted/targeted proteins and 242 transmembrane proteins. The codon adaptation indices of the identified proteins suggested that the system could identify proteins of relatively low abundance, which are difficult to identify by conventional 2D-gel electrophoresis (GE) followed by an offline mass spectrometric analysis such as peptide mass fingerprinting. Among the similar to5400 peptides assigned in this study, many peptides with post-translational modifications, such as N-terminal acetylation and phosphorylation, were detected. This expression profile of C. elegans, containing 571 hypothetical gene products, will serve as the basic data of a major proteome set expressed in the worm.