Hartman PS et al. (1982) Mol Gen Genet "Somatic damage to the X chromosome of the nematode Caenorhabditis elegans induced by gamma radiation."

Hartman PS, Herman RK

[Mol Gen Genet, 1982]

Wild-type male embryos and young larvae of the nematode Caenorhabditis elegans were more sensitive than wild-type hermaphrodites to inactivation by gamma rays; wild-type males have one X chromosome per cell (XO), whereas wild-type hermaphrodites have two (XX). Furthermore, after transformation into fertile hermaphrodites by a her-1 mutation, XO animals were more radiosensitive than XX her-1 animals; and XX animals transformed into fertile males by a tra-1 mutation did not show increased radiosensitivity. It is concluded that wild-type males are more radiosensitive than wild-type hermaphrodites because they have one X chromosome rather than two, and the predominant mode of inactivation of XO animals involves damage to the single X chromosome. No sex- specific differences in survival were observed after UV irradiation.

Ackley BD (2019) Curr Biol "Behavior: Should I Stay or Should I Go?"

Ackley BD

[Curr Biol, 2019]

Laboratory-conditioned 'wild-type' Caenorhabditis elegans are different from wild-isolated strains. Now it seems some differences lead lab-conditioned animals to act irrationally after experiencing starvation early in development. This increases the repertoire of behaviors we can study with these fascinating animals.

Ishii N et al. (1990) Mutat Res "A methyl viologen-sensitive mutant of the nematode Caenorhabditis elegans."

Ishii N, Honda S, Tomita S, Suzuki K, Keino T, Yoshino K, Takahashi K

[Mutat Res, 1990]

A methyl viologen (paraquat)-sensitive mutant, mev-1 (LG III), in Caenorhabditis elegans was about 4 times more sensitive to methyl viologen than the wild type. This mutant was also hypersensitive to oxygen. The brood size was about 1/4 that of the wild type. The average life span was determined to be 9.3 days as compared to 14.3 days for the wild type. The activity of superoxide dismutase (SOD), a scavenging enzyme for superoxide anion, was about half the wild-type level. We suggest that oxygen radicals may be involved in the normal aging mechanism in C. elegans.

Ralph Menzel et al. (2008) European Worm Meeting "Humic material induces behavioral and transcriptional responses in the nematode Caenorhabditis elegans and extends its lifespan"

Heike Staudacher, Ralph Menzel, Kerstin Pietsch, Stefanie Rienau, Christian E W Steinberg, Waltraud Wild, Nadine Saul

[European Worm Meeting, 2008]

Humic substances (HS) are complex organic molecules constituting the most. abundant source of natural organic matter (NOM) in freshwater and soil. ecosystems. They are taken up by organisms and interact on various. molecular and biochemical levels. Recent advances have identified that they. interfere with biological systems, via the induction of biotransformation. enzymes and the production of internal oxidative stress.. The nematode model organism Caenorhabditis elegans was chosen to. investigate whether natural and synthetic HS induce (i) a behavioral. attraction, (ii) the reproduction, (iii) an increased lifespan, and (iv) a. response in transcriptional expression. The phenomenological attractant. experiments provided evidence that HS attract the worm and exert distinct. chemical cues. In the reproduction assay, only the highest concentration. (30 mg/L dissolved organic carbon) resulted in a slight decrease in brood. size, highlighting an overall intrinsic tolerance towards humic material.. Lifespan experiments showed that at least one HS increases the lifespan of. Caenorhabditis elegans. Finally, DNA array experiments were performed from. control and HS treated worms. Significant transcriptional changes. (exceeding a two-fold in- or decrease) were identified and in chemosensors,. olfactory receptors, as well as enzymes of the biotransformation system. (glutathione S-transferases, short-chain dehydrogenases) and. vitellogenines. The results were proved by quantitative real-time RT-PCR,. thereby confirming that humic material is recognized as an environmental. signaling chemical.

Lee Y et al. (2016) Aging (Albany NY) "Inverse correlation between longevity and developmental rate among wild C. elegans strains."

Lee Y, Kim PJ, Jung J, Hwang W, Cabatbat JJ, Park S, Lee SV

[Aging (Albany NY), 2016]

Genetic studies using model organisms have shown that many long-lived mutants display impaired fitness, such as reduced fecundity and delayed development. However, in several wild animals, the association between longevity and fitness does not seem to be inevitable. Thus, the relationship between longevity and fitness in wild organisms remains inconclusive. Here, we determined the correlation between lifespan and fitness, developmental rate and brood size, by using 16 wild-derived C. elegans strains originated from various geographic areas. We found a negative correlation between lifespan and developmental rate. In contrast, we did not find such negative correlation between longevity and developmental rate among the individuals of C. elegans strains. These data imply that polymorphic genetic variants among wild isolates determine resource allocation to longevity and developmental rate.

Suthakaran, Nirthieca et al. (2022) MicroPubl Biol

Dawson-Scully , Ken, Suthakaran, Nirthieca, Gonzalez- Lerma, Paola, Brock , Trisha, Naraine, Akshay, Hopkins, Chris

[MicroPubl Biol, 2022]

Atropine has been used as an established anticonvulsant treatment for nerve agent intoxication. Atropine reduces electroshock recovery time among aldicarb-exposed wild-type C. elegans .

Bhat SG et al. (1980) Mol Gen Genet "Mutagen sensitivity of kynureninase mutants of the nematode Caenorhabditis elegans."

Babu P, Bhat SG

[Mol Gen Genet, 1980]

Mutants in the gene flu-2 of the free-living nematode Caenorhabditis elegans are characterised by an altered autofluorescence of the intestine cells, from the light blue of wild-type to a dull green colour. The properties of flu-2 mutants have been investigated. L- kynureninase activity has been detected in wild-type C. elegans. The flu-2 mutants have markedly reduced kynureninase activity, as predicted earlier from chromatographic analysis of tryptophan catabolites of wild-type and mutant worms. Associated with this enzymatic block, all flu-2 mutants have enhanced sensitivity to ethyl methane sulfonate (EMS)

(1976) Worm Breeder's Gazette "levamisole-resistant mutants with a wild type visible phenotype."

[Worm Breeder's Gazette, 1976]

As described by Brenner, a large fraction of levamisole-resistant mutants are worms with a wild type visible phenotype when grown on NG plates. We find that most of these mutants grown in the presence of levamisole acquire the peculiar uncoordinated phenotype characteristic of the levamisole-resistant uncs. In our cut worm assay, several of these 'wild type' mutant strains showed near wild type susceptibility to all drugs tested (including levamisole) when grown in the absence of levamisole. Grown and tested in the presence of levamisole, the worms showed extreme resistance to cholinergic agonists but sensitivity to the muscle contracting agent ouabain. The latter pharmacological phenotype is characteristic of levamisole-resistant uncs and N2 wild type worms treated with cholinergic blocking agents. As we mentioned previously, levamisole also acts as an agonist on naive worms and is blocked by cholinergic antagonists. From these observations, we infer that levamisole is a cholinergic depolarizing blocking agent. We believe that mutants with a normal visible phenotype have less of and/or less functional acetylcholine receptors than the wild type-but still workable receptors. Possibly, levamisole depolarizes in binding to the Ac receptor but once bound, has a blocking effect. N2 wild type worms grown on levamisole would always have a significant amount of muscle-depolarization due to constant dissociation and reassociation of levamisole with the receptor, whereas the wild type mutants would have an insignificant absolute amount of receptor undergoing this flux-hence only the blocking effect is seen after recovery from initial exposure to the drug. By far the largest fraction and the most resistant 'wild type' mutants fall into a gene probably corresponding to tmr-1 described by Brenner. Very rare mutants in this gene are levamisole-resistant uncs when homozygous and semi-dominant in the growth test on levamisole! Most of the other wild type mutants appear to be leaky alleles of the levamisole-resistant unc loci. A couple of rare birds are sex-linked and apparently sexually dimorphic. Four rather different mutants have been isolated with close to wild type visible phenotype and extreme resistance to levamisole even when grown in the absence of the drug. In the cut worm assay they show extreme resistance to levamisole and varying susceptibility to other cholinergic agonists (unfortunately not a wild type susceptibility to acetylcholine). These might be mutants having the minimal amount of functional Ac receptor necessary for a wild type visible phenotype; we prefer to think that they are acetylcholine binding protein mutants. Three of the four mutants are in unc-29, LG I.

Stobierska J et al. (2025) MicroPubl Biol "Low-fecundity dhc-1; mel-28 C. elegans mutants do not have gonad mitosis defects."

Stobierska J, Fernandez AG

[MicroPubl Biol, 2025]

In <i>C. elegans , dhc-1 ( or283 ); mel-28 ( t1684 )</i> double mutants have a severely reduced brood size compared with each single mutant and compared to the wild type. To determine if this synthetic low-fecundity phenotype is due to reduced potential to produce gametes, we studied gonad length and distal gonad mitotic activity in <i>dhc-1 ( or283 )</i> mutants, <i>mel-28 ( t1684 )</i> mutants, wild-type animals, and <i>dhc-1 ( or283 ); mel-28 ( t1684 )</i> double mutants. Gonad length in <i>dhc-1 ; mel-28</i> double mutants was the same as the wild type. Using an antibody against phosphorylated histone H3 (PH3), we tracked mitotic activity in mutant and wild-type gonads. We found no significant difference in mitotic activity between the double mutant and the wild-type. These observations suggest that the reduced brood size in <i>dhc-1 ; mel-28</i> double mutants is not caused by a mitotically-inactive gonad and instead has a different and yet-to-be-determined basis.

Chen J et al. (2001) Exp Gerontol "Comparative demography of isogenic populations of Caenorhabditis elegans."

Chen J, Carey JR, Ferris H

[Exp Gerontol, 2001]

Demographic characteristics of the bacterial-feeding nematode Caenorhabditis elegans were determined in two long-lived mutant strains, TJ1052 (age-1), CB4876 (clk-1), and a wild-type strain, N2. Within each strain, there was little correlation between longevity and reproduction for individuals that lived longer than 10 days. Long-lived mutant strains produced fewer eggs than the wild type. Mean total life spans were 13.2 days for the wild type, 21.9 days for age-1, and 15.8 days for clk-1; maximum life spans were 24 days for the wild type, 47 days for age-1, and 32 days for clk-1. Differences in total life span resulted primarily from longer post-reproductive survival. The mean post-reproductive life spans were longer than the wild type by 183% in age-1 and 60% in clk-1. We conclude that (i) post-reproductive survival is not correlated with egg production within isogenic populations of C. elegans, and (ii) the relationship between reproduction and longevity differs among isogenic populations with specific longevity genes.