Mathies, Laura D et al. (2022) MicroPubl Biol

Blackwell, GinaMari, Mathies, Laura D, Bettinger, Jill C

[MicroPubl Biol, 2022]

SWI/SNF chromatin remodeling complexes regulate many aspects of metazoan development and mutations in SWI/SNF genes are associated with diverse human diseases including cancer and alcohol use disorder. In C. elegans, SWI/SNF subunits are required for viability, somatic gonad development, and normal behavioral responses to ethanol. SWI/SNF complexes can be classified as BAF (BRG1/Brm-associated factors) or PBAF (Polybromo-associated BAF) based on their subunit composition. While there are loss-of-function alleles for most SWI/SNF family members, strong loss of function mutations have not previously been reported for the PBAF gene phf-10. Here we describe two new alleles of phf-10 that we generated using CRISPR/Cas9 genome editing.

Shoman LM et al. (1994) Worm Breeder's Gazette "Worm Community System Users Envision Future Application."

Grossman E, Shoman LM, Jamison DC, Schatz BR

[Worm Breeder's Gazette, 1994]

Worm Community System Users Envision Future Application. Laura Shoman, Curt Jamison, Ed Grossman, Bruce Schatz, Community Systems Laboratory, National Center for Supercomputing Applications, University of Illinois, Urbana- Champaign, 405 North Mathews, Urbana, IL 61801 (wcs@csl.ncsa.uiuc.edu)

Sakoguchi H et al. (2016) Biosci Biotechnol Biochem "Screening of biologically active monosaccharides: growth inhibitory effects of d-allose, d-talose, and l-idose against the nematode Caenorhabditis elegans."

Izumori K, Yoshihara A, Sakoguchi H, Sato M

[Biosci Biotechnol Biochem, 2016]

We compared the growth inhibitory effects of all aldohexose stereoisomers against the model animal Caenorhabditis elegans. Among the tested compounds, the rare sugars d-allose (d-All), d-talose (d-Tal), and l-idose (l-Ido) showed considerable growth inhibition under both monoxenic and axenic culture conditions. 6-Deoxy-d-All had no effect on growth, which suggests that C6-phosphorylation by hexokinase is essential for inhibition by d-All.

Sakoguchi H et al. (2016) Bioorg Med Chem Lett "Growth inhibitory effect of d-arabinose against the nematode Caenorhabditis elegans: Discovery of a novel bioactive monosaccharide."

Shintani T, Izumori K, Sato M, Sakoguchi H, Okuma K, Yoshihara A

[Bioorg Med Chem Lett, 2016]

Biological activities of unusual monosaccharides (rare sugars) have largely remained unstudied until recently. We compared the growth inhibitory effects of aldohexose stereoisomers against the animal model Caenorhabditis elegans cultured in monoxenic conditions with Escherichia coli as food. Among these stereoisomers, the rare sugar d-arabinose (d-Ara) showed particularly strong growth inhibition. The IC50 value for d-Ara was estimated to be 7.5mM, which surpassed that of the potent glycolytic inhibitor 2-deoxy-d-glucose (19.5mM) used as a positive control. The inhibitory effect of d-Ara was also observed in animals cultured in axenic conditions using a chemically defined medium; this excluded the possible influence of E. coli. To our knowledge, this is the first report of biological activity of d-Ara. The d-Ara-induced inhibition was recovered by adding either d-ribose or d-fructose, but not d-glucose. These findings suggest that the inhibition could be induced by multiple mechanisms, for example, disturbance of d-ribose and d-fructose metabolism.

Yoshihara A et al. (2019) Bioorg Med Chem Lett "Growth inhibition by 1-deoxy-d-allulose, a novel bioactive deoxy sugar, screened using Caenorhabditis elegans assay."

Sakoguchi H, Fleet GWJ, Izumori K, Shintani T, Sato M, Yoshihara A

[Bioorg Med Chem Lett, 2019]

The biological activities of deoxy sugars (deoxy monosaccharides) have remained largely unstudied until recently. We compared the growth inhibition by all 1-deoxyketohexoses using the animal model Caenorhabditis elegans. Among the eight stereoisomers, 1-deoxy-d-allulose (1d-d-Alu) showed particularly strong growth inhibition. The 50% inhibition of growth (GI₅₀) concentration by 1d-d-Alu was estimated to be 5.4mM, which is approximately 10 times lower than that of d-allulose (52.7mM), and even lower than that of the potent glycolytic inhibitor, 2-deoxy-d-glucose (19.5mM), implying that 1d-d-Alu has a strong growth inhibition. In contrast, 5-deoxy- and 6-deoxy-d-allulose showed no growth inhibition of C. elegans. The inhibition by 1d-d-Alu was alleviated by the addition of d-ribose or d-fructose. Our findings suggest that 1d-d-Alu-mediated growth inhibition could be induced by the imbalance in d-ribose metabolism. To our knowledge, this is the first report of biological activity of 1d-d-Alu which may be considered as an antimetabolite drug candidate.

Katane M et al. (2020) Biochim Biophys Acta Proteins Proteom "Biochemical characterization of d-aspartate oxidase from Caenorhabditis elegans: Its potential use in the determination of free D-glutamate in biological samples."

Katane M, Sekine M, Nakayama K, Homma H, Kuwabara H, Saitoh Y, Miyamoto T

[Biochim Biophys Acta Proteins Proteom, 2020]

d-Aspartate oxidase (DDO) is a flavin adenine dinucleotide (FAD)-containing flavoprotein that stereospecifically acts on acidic D-amino acids (i.e., free d-aspartate and D-glutamate). Mammalian DDO, which exhibits higher activity toward d-aspartate than D-glutamate, is presumed to regulate levels of d-aspartate in the body and is not thought to degrade D-glutamate in vivo. By contrast, three DDO isoforms are present in the nematode Caenorhabditis elegans, DDO-1, DDO-2, and DDO-3, all of which exhibit substantial activity toward D-glutamate as well as d-aspartate. In this study, we optimized the Escherichia coli culture conditions for production of recombinant C. elegans DDO-1, purified the protein, and showed that it is a flavoprotein with a noncovalently but tightly attached FAD. Furthermore, C. elegans DDO-1, but not mammalian (rat) DDO, efficiently and selectively degraded D-glutamate in addition to d-aspartate, even in the presence of various other amino acids. Thus, C. elegans DDO-1 might be a useful tool for determining these acidic D-amino acids in biological samples.

Shintani T et al. (2019) J Appl Glycosci (1999) "D-Allose, a Stereoisomer of D-Glucose, Extends the Lifespan of Caenorhabditis elegans via Sirtuin and Insulin Signaling."

Izumori K, Sakoguchi H, Yoshihara A, Shintani T, Sato M

[J Appl Glycosci (1999), 2019]

D-Allose (D-All), C-3 epimer of D-glucose, is a rare sugar known to suppress reactive oxygen species generation and prevent hypertension. We previously reported that D-allulose, a structural isomer of D-All, prolongs the lifespan of the nematode Caenorhabditis elegans. Thus, D-All was predicted to affect longevity. In this study, we provide the first empirical evidence that D-All extends the lifespan of C. elegans. Lifespan assays revealed that a lifespan extension was induced by 28 mM D-All. In particular, a lifespan extension of 23.8 % was achieved (p< 0.0001). We further revealed that the effects of D-All on lifespan were dependent on the insulin gene daf-16 and the longevity gene sir-2.1, indicating a distinct mechanism from those of other hexoses, such as D-allulose, with previously reported antiaging effects.

Sato M et al. (2008) J Nat Med "Potential anthelmintic: D-psicose inhibits motility, growth and reproductive maturity of L1 larvae of Caenorhabditis elegans."

Izumori K, Yamasaki T, Kurose H, Sato M

[J Nat Med, 2008]

No anthelmintic sugars have yet been identified. Eight ketohexose stereoisomers (D- and L-forms of psicose, fructose, tagatose and sorbose), along with D-galactose and D-glucose, were examined for potency against L1 stage Caenorhabditis elegans fed Escherichia coli. Of the sugars, D-psicose specifically inhibited the motility, growth and reproductive maturity of the L1 stage. D-Psicose probably interferes with the nematode nutrition. The present results suggest that D-psicose, one of the rare sugars, is a potential anthelmintic.

Davies, Andrew G. et al. (2017) International Worm Meeting "A genetic screen for mediators of acute alcohol effects."

Blackwell, GinaMari G., Davies, Andrew G., Bettinger, Jill C., Mathies, Laura D.

[International Worm Meeting, 2017]

The behavioral effects associated with the consumption of alcohol (ethanol) in humans reflect the summation of many interactions of alcohol with a variety of protein targets. We are using C. elegans to identify individual mechanisms of action of alcohol with the idea that molecular interactions between alcohol and a target protein are likely to be conserved across species. We have used a forward genetic approach to screen for new mutations that produce decreased sensitivity to the locomotor-depressing effects of alcohol. Using genetic mapping and whole-genome sequencing, we have identified two new alcohol resistance genes, nep-2 and lgc-31. nep-2 encodes a metallo-endopeptidase that appears to act by cleaving peptides, including the peptide encoded by the snet-1 gene (Yamada et al. 2010 Science 329:1647). Loss-of-function mutations in nep-2 result in alcohol resistance, which is consistent with the idea that one or more peptides cleaved by NEP-2 act via a neuropeptide receptor to counter an action of alcohol. A snet-1 mutation only partially suppresses the nep-2 alcohol resistance, demonstrating that SNET-1 is not the only relevant NEP-2 target peptide. We are screening neuropeptide receptor genes to identify the receptor that mediates this action with the assumption that a mutation in the receptor-encoding gene should suppress the nep-2-induced alcohol resistance. Loss-of-function mutations in the ligand-gated ion channel-encoding gene, lgc-31, produce an alcohol resistance phenotype. Receptors of this class (GABA, ACh, glycine) are commonly cited as alcohol targets in mammalian studies. We are pursuing the possibility that ethanol activates the LGC-31 channel directly, by altering specific amino acids in the 2nd transmembrane domain, which have been shown in related channels to alter ethanol-related activation properties. The ligand for LGC-31 is not known; we are testing possible ligands based on the orthology of lgc-31 to the human zinc-activated channel gene (ZACN) and the serotonin-gated ion channel gene (HTR3D). Knowledge of the range of molecular actions of alcohol will allow for the identification of genetic factors that predispose individuals to develop alcohol use disorders.

Yasuaki Saitoh et al. (2010) East Asia Worm Meeting "Study on physiological functions of D-amino acid degradative enzymes in nematode Caenorhabditis elegans"

Yousuke Seida, Kazuhiro Maeda, Tomonori Kawata, Masumi Katane, Hiroyuki Kobuna, Takao Inoue, Yasuaki Saitoh, Hiroyuki Arai, Yasuhito Nakagawa, Masae Sekine, Taro Sakamoto, Hiroshi Homma, Takemitsu Furuchi

[East Asia Worm Meeting, 2010]

Among free D-amino acids existing in living organisms, D-serine (D-Ser) and D-aspartate (D-Asp) are the most actively studied. D-Ser has been proposed as a neuromodulator that regulates L-glutamate-mediated activation of the N-methyl-D-Asp (NMDA) receptor by acting as a co-agonist. On the other hand, several lines of evidence suggest that D-Asp plays important roles in regulating developmental processes, hormone secretion and steroidogenesis. D-Amino acid oxidase (DAO) and D-Asp oxidase (DDO) are known as stereospecific degradative enzymes that catalyze the oxidative deamination of D-amino acids. DAO displays broad substrate specificity and acts on several neutral and basic D-amino acids, while DDO is highly specific for acidic D-amino acids. DAO and DDO are presumed to regulate endogenous D-Ser and D-Asp levels, respectively, as well as mediate the elimination of accumulated exogenous D-amino acids in various organs. Previously, we demonstrated that nematode Caenorhabditis elegans, a multicellular model animal has at least one active DAO gene and three active DDO genes, while it had been thought that most organisms bear only one copy of each DAO and DDO gene. In addition, our previous study revealed that the spatiotemporal distributions of these enzymes in the body of C. elegans are different from one another. In this study, to elucidate the physiological roles of the C. elegans DAO and DDOs, we characterized several phenotypes of four C. elegans mutants in which each gene is partially deleted and inactivated. We also determined free D-amino acid contents in several worm samples using high-performance liquid chromatography (HPLC) techniques. We will report the phenotypes of the C. elegans mutants in comparison with those of wild-type C. elegans, as well as alterations in D-amino acid levels within the body.