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[
Elife,
2018]
A diverse array of species on the planet employ the Earth's magnetic field as a navigational aid. As the majority of these animals are migratory, their utility to interrogate the molecular and cellular basis of the magnetic sense is limited. Vidal-Gadea and colleagues recently argued that the worm <i>Caenorhabditis elegans</i> possesses a magnetic sense that guides their vertical movement in soil. In making this claim, they relied on three different behavioral assays that involved magnetic stimuli. Here, we set out to replicate their results employing blinded protocols and double wrapped coils that control for heat generation. We find no evidence supporting the existence of a magnetic sense in <i>C. elegans</i>. We further show that the Vidal-Gadea hypothesis is problematic as the adoption of a correction angle and a fixed trajectory relative to the Earth's magnetic inclination does not necessarily result in vertical movement.
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[
Science,
2000]
Protein interaction mapping using large-scale two-hybrid analysis has been proposed as a way to functionally annotate large numbers of uncharacterized proteins predicted by complete genome sequences. This approach was examined in Caenorhabditis elegans, starting with 27 proteins involved in vulval development. The resulting map reveals both known and new potential interactions and provides a functional annotation for approximately 100 uncharacterized gene products. A protein interaction mapping project is now feasible for C. elegans on a genome-wide scale and should contribute to the understanding of molecular mechanisms in this organism and in human diseases.AD - Massachusetts General Hospital Cancer Center, Charlestown, MA 02129, USA.FAU - Walhout, A JAU - Walhout AJFAU - Sordella, RAU - Sordella RFAU - Lu, XAU - Lu XFAU - Hartley, J LAU - Hartley JLFAU - Temple, G FAU - Temple GFFAU - Brasch, M AAU - Brasch MAFAU - Thierry-Mieg, NAU - Thierry-Mieg NFAU - Vidal, MAU - Vidal MLA - engID - 1 R21 CA81658 A 01/CA/NCIID - 1 RO1 HG01715-01/HG/NHGRIPT - Journal ArticleCY - UNITED STATESTA - ScienceJID - 0404511RN - 0 (Genetic Vectors)RN - 0 (Helminth Proteins)RN - 0 (LIN-35 protein)RN - 0 (LIN-53 protein)RN - 0 (Repressor Proteins)RN - 0 (Retinoblastoma Protein)SB - IM
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[
J Neurophysiol,
2015]
Although the ability to detect humidity (i.e., hygrosensation) represents an important sensory attribute in many animal species (including humans), the neurophysiological and molecular bases of such sensory ability remain largely unknown in many animals. Recently, Russell and colleagues (Russell J, Vidal-Gadea AG, Makay A, Lanam C, Pierce-Shimomura JT. Proc Natl Acad Sci USA 111: 8269-8274, 2014) provided for the first time neuromolecular evidence for the sensory integration of thermal and mechanical sensory cues which underpin the hygrosensation strategy of an animal (i.e., the free-living roundworm Caenorhabditis elegans) that lacks specific sensory organs for humidity detection (i.e., hygroreceptors). Due to the remarkable similarities in the hygrosensation transduction mechanisms used by hygroreceptor-provided (e.g., insects) and hygroreceptor-lacking species (e.g., roundworms and humans), the findings of Russell et al. highlight potentially universal mechanisms for humidity detection that could be shared across a wide range of species, including humans.
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[
Elife,
2018]
Many animals can orient using the earth's magnetic field. In a recent study, we performed three distinct behavioral assays providing evidence that the nematode <i>Caenorhabditis elegans</i> orients to earth-strength magnetic fields (<xref ref-type="bibr" rid="
bib28">Vidal-Gadea et al., 2015</xref>). A new study by Landler et al. suggests that <i>C. elegans</i> does not orient to magnetic fields (<xref ref-type="bibr" rid="
bib10">Landler et al., 2018</xref>). They also raise conceptual issues that cast doubt on our study. Here, we explain how they appear to have missed positive results in part by omitting controls and running assays longer than prescribed, so that worms switched their preferred migratory direction within single tests. We also highlight differences in experimental methods and interpretations that may explain our different results and conclusions. Together, these findings provide guidance on how to achieve robust magnetotaxis and reinforce our original finding that <i>C. elegans</i> is a suitable model system to study magnetoreception.
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Doucette-Stamm L, Lamesch PE, Reboul J, Temple GF, Hartley JL, Brasch MA, Hill DE, Vaglio P, Thierry-Mieg N, Shin-i T, Lee H, Moore T, Vandenhaute J, Kohara Y, Vidal M, Jackson C, Thierry-Mieg J, Tzellas N, Thierry-Mieg D, Hitti J
[
Nat Genet,
2001]
The genome sequences of Caenorhabditis elegans, Drosophila melanogaster and Arabidopsis thaliana have been predicted to contain 19,000, 13,600 and 25,500 genes, respectively. Before this information can be fully used for evolutionary and functional studies, several issues need to be addressed. First, the gene number estimates obtained in silico and not yet supported by any experimental data need to be verified. For example, it seems biologically paradoxical that C. elegans would have 50% more genes than Drosophilia. Second, intron/exon predictions need to be tested experimentally. Third, complete sets of open reading frames (ORFs), or "ORFeomes," need to be cloned into various expression vectors. To address these issues simultaneously, we have designed and applied to C. elegans the following strategy. Predicted ORFs are amplified by PCR from a highly representative cDNA library using ORF-specific primers, cloned by Gateway recombination cloning and then sequenced to generate ORF sequence tags (OSTs) as a way to verify identity and splicing. In a sample (n=1,222) of the nearly 10,000 genes predicted ab initio (that is, for which no expressed sequence tag (EST) is available so far), at least 70% were verified by OSTs. We also observed that 27% of these experimentally confirmed genes have a structure different from that predicted by GeneFinder. We now have experimental evidence that supports the existence of at least 17,300 genes in C. elegans. Hence we suggest that gene counts based primarily on ESTs may underestimate the number of genes in human and in other organisms.AD - Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA.FAU - Reboul, JAU - Reboul JFAU - Vaglio, PAU - Vaglio PFAU - Tzellas, NAU - Tzellas NFAU - Thierry-Mieg, NAU - Thierry-Mieg NFAU - Moore, TAU - Moore TFAU - Jackson, CAU - Jackson CFAU - Shin-i, TAU - Shin-i TFAU - Kohara, YAU - Kohara YFAU - Thierry-Mieg, DAU - Thierry-Mieg DFAU - Thierry-Mieg, JAU - Thierry-Mieg JFAU - Lee, HAU - Lee HFAU - Hitti, JAU - Hitti JFAU - Doucette-Stamm, LAU - Doucette-Stamm LFAU - Hartley, J LAU - Hartley JLFAU - Temple, G FAU - Temple GFFAU - Brasch, M AAU - Brasch MAFAU - Vandenhaute, JAU - Vandenhaute JFAU - Lamesch, P EAU - Lamesch PEFAU - Hill, D EAU - Hill DEFAU - Vidal, MAU - Vidal MLA - engID - R21 CA81658 A 01/CA/NCIID - RO1 HG01715-01/HG/NHGRIPT - Journal ArticleCY - United StatesTA - Nat GenetJID - 9216904SB - IM
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[
J Neurosci Methods,
2016]
BACKGROUND: The study of locomotion in vermiform animals has largely been restricted to animals crawling on agar surfaces. While this has been fruitful in the study of neuronal basis of disease and behavior, the reduced physical challenge posed by these environments has prevented these organisms from being equally successful in the study of neuromuscular diseases. Our burrowing assay allowed us to study the effects of muscular exertion on locomotion and muscle degeneration during disease (Beron et al., 2015), as well as the natural burrowing preference of diverse C. elegans strains (Vidal-Gadea et al., 2015). NEW METHOD: We describe a simple, rapid, and affordable set of assays to study the burrowing behavior of nematodes and other vermiform organisms which permits the titration of muscular exertion in test animals. RESULTS: We show that our burrowing assay design is versatile and can be adapted for use in widely different experimental paradigms. COMPARISON WITH EXISTING METHOD(S): Previous assays for the study of neuromuscular integrity in nematodes relied on movement through facile and homogeneous environments. The ability of modulating substrate density allows our burrowing assay to be used to separate animal populations where muscular fitness or health are not visible differentiable by standard techniques. CONCLUSION: The simplicity, versatility, and potential for greatly facilitating the study of previously challenging neuromuscular disorders makes this assay a valuable addition that overcomes many of the limitations inherent to traditional behavioral tests of vermiform locomotion.
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[
MicroPubl Biol,
2021]
Parkinson's disease (PD) patients have been shown to benefit greatly from intense physical activity (Schenkman et al. 2018). Recent studies have demonstrated that exercise causes changes in the levels of alpha-synuclein aggregate species, a hallmark of PD, in different mammalian animal models (Koo and Cho 2017; Shin et al. 2017; Zhou et al. 2017; Minakaki et al. 2019). However, questions still remain about how exercise affects specifically native alpha-synuclein protein species directly after the cessation of exercise and the longer-term downstream effects which exercise may have on organismal health. It was recently discovered that periods of thrashing in liquid solution, otherwise called swimming exercise, in C. elegans worms, induces many mechanisms invoked during mammalian exercise (Laranjeiro et al. 2017). This has provided an avenue for studying exercise conditions in various C. elegans models of neurodegeneration (Laranjeiro et al. 2019). In order to study the effect of exercise on native human alpha-synuclein protein species, we utilized the NL5901- pkIs2386 worm model of Parkinson's which contains human alpha-synuclein tagged to a yellow fluorescent protein (YFP) in the muscle cells (van Ham et al. 2008). We performed tissue analysis via Blue Native (BN) page westerns and confocal microscopy. In addition, because pharyngeal pumping is decreased while worms are swimming, we controlled for this effect by exposing worms in parallel to a period of food restriction (FR) conditions (Vidal-Gadea et al. 2012). We also performed thrashing assays to assess longer term downstream behavioral effects on the animals after either exercise or food restriction conditions.
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[
MicroPubl Biol,
2021]
From the beginning of Caenorhabditis elegans inception as a genetic model organism by Sydney Brenner (Brenner 1974), the ability to measure and quantify behavior in these nematodes led to numerous and powerful insights (Apfeld et al. 2018). The experimental amenability of worms makes them not just superb research subjects but also useful pedagogical tools. While excellent classroom additions to illustrate many biological processes, the educational potential of worms has lagged due to the expensive equipment required for their study. In most educational settings, lack of equipment discourages individual exploration and falls short of the promise owed to young and driven students. One of the places where this is felt strongly is in the automated quantification of animal behavior. Many systems have been developed over the years (and are currently used across the world) for the rapid and unbiased quantification of behavioral phenotypes. For example, we used tracking systems to compare the ability of mutant C. elegans strains to transition between gaits (Vidal-Gadea et al., 2011), and Deng and colleagues used them to study the role of inhibitory GABAergic motorneurons during rapid locomotion (Deng et al., 2020, see Husson et al. 2012 for a review of the use of tracking systems in C. elegans). Until recently, the automated quantification of C. elegans behavior was only feasible in specialized labs. Recent advances have begun to reduce the expense and complexity of automatically quantifying animal behavior. For example, the Haspel lab at NJIT made use of the recently developed Tierpsy behavioral software (Avelino et al. 2018) to build numerous animal tracking systems that are user friendly, and able to achieve levels of kinematic analysis that previously required considerably more expensive setups (Deng et al. 2020).