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[
Curr Biol,
2015]
The fundamental importance of neuronal connectivity for neural function has stimulated brain-mapping efforts in several organisms. In the nematode Caenorhabditis elegans an essentially complete wiring diagram has been available for nearly thirty years. To identify neglected, but well-connected neurons of C. elegans we used online activity and literature searches to rank 'popularity'. Cross-referencing this list with a topological analysis of the connectome, DVC emerged as the worm's most understudied hub neuron. We found that optogenetic activation of DVC promotes backward locomotion and that this response is dependent on the vesicular glutamate transporter, EAT-4.
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[
BMC Genomics,
2010]
BACKGROUND: In recent years numerous studies have undertaken to measure the impact of patents, material transfer agreements, data-withholding and commercialization pressures on biomedical researchers. Of particular concern is the theory that such pressures may have negative effects on academic and other upstream researchers. In response to these concerns, commentators in some research communities have called for an increased level of access to, and sharing of, data and research materials. We have been studying how data and materials are shared in the community of researchers who use the nematode Caenorhabditis elegans (C. elegans) as a model organism for biological research. Specifically, we conducted a textual analysis of academic articles referencing C. elegans, reviewed C. elegans repository request lists, scanned patents that reference C. elegans and conducted a broad survey of C. elegans researchers. Of particular importance in our research was the role of the C. elegans Gene Knockout Consortium in the facilitation of sharing in this community. RESULTS: Our research suggests that a culture of sharing exists within the C. elegans research community. Furthermore, our research provides insight into how this sharing operates and the role of the culture that underpins it. CONCLUSIONS: The greater scientific community is likely to benefit from understanding the factors that motivate C. elegans researchers to share. In this sense, our research is a 'response' to calls for a greater amount of sharing in other research communities, such as the mouse community, specifically, the call for increased investment and support of centralized resource sharing infrastructure, grant-based funding of data-sharing, clarity of third party recommendations regarding sharing, third party insistence of post-publication data sharing, a decrease in patenting and restrictive material transfer agreements, and increased attribution and reward.
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[
Curr Biol,
2000]
During signaling by the Notch receptor, Notch's intracellular domain is cleaved, moves to the nucleus and associates with a DNA-binding protein of the CSL class (CSL for CBF1, Suppressor of Hairless (Su(H)), LAG-1); as a result, target genes are transcriptionally activated (reviewed in [1,2]). In Caenorhabditis elegans, a glutamine-rich protein called LAG-3 forms a ternary complex with the Notch intracellular domain and LAG-1 and appears to serve as a transcriptional activator that is critical for signaling [3]. Although database searches failed to identify a LAG-3-related protein, we surmised that Notch signaling in other organisms might involve an analogous activity.
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[
Science,
1977]
At a recent conference in Woods Hole, Massachusetts, investigators met to discuss the nematode Caenorhabditis elegans. This free-living worm may, according to some workers, become the Escherichia coli or at least the bacteriophage T4 of the animal world. Small (about 1mm in length) and semitransparent, C. elegans provides for research the advantages of a short life cycle (3 days) and a simple anatomy-it contains about 810 nongonadal nuclei. It is both easy to cultivate, on E. coli as a food source, and convenient for genetic analysis. Its genes are carried on five autosomes and a sex chromosome (X), and it has a genome size about 20 times that of E. coli. It generally reproduces as a self-fertilizing hermaphrodite (XX), but occasional males (XO), which arise by nondisjunction, permit sexual reproduction as well....
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[
Neuromuscul Disord,
2004]
In her commentary on our recently published paper, A. de Luca questions the approach consisting in screening random molecules on a dystrophin-deficient invertebrate model (C. elegans) in order to identify potential therapeutic clues.
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[
J Mol Evol,
1996]
Transmembrane 4 superfamily (TM4SF) molecules are predominantly mammalian cell surface glycoproteins that are thought to transduce signals mediating cell development, activation, and motility. Analysis of the Genpept sequence database reveals YKK8, a novel member of the TM4SF in the nematode, Caenorhabditis elegans. YKK8 is a putative 27.4-kDa protein encoded by a gene on chromosome III of the C. elegans genome. The assignment of YKK8 to the TM4SF is justified by three criteria: statistical comparison of protein sequences, conserved TM4SF protein sequence motifs, and conserved TM4SF intron/exon boundaries in the genomic sequence. The discovery of a TM4SF molecule in the nematode extends this superfamily to a more primitive branch of the phylogenetic tree and suggests a fundamental role for TM4SF molecules in biology.
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[
ACS Chem Biol,
2011]
MicroRNAs (miRNAs) are small non-coding RNAs that play numerous important roles in physiology and human diseases. During animal development, many miRNAs are expressed continuously from early embryos throughout adults, yet it is unclear whether these miRNAs are actually required at all the stages of development. Current techniques of manipulating microRNA function lack the required spatial and temporal resolution to adequately address the functionality of a given microRNA at a specific time or at single-cell resolution. To examine stage- or cell-specific function of miRNA during development and to achieve precise control of miRNA activity, we have developed photoactivatable antisense oligonucleotides against miRNAs. These caged oligonucleotides can be activated with 365 nm light with extraordinarily high efficiency to release potent antisense reagents to inhibit miRNAs. Initial application of these caged antimirs in a model organism (C. elegans) revealed that the activity of a miRNA (
lsy-6) is required specifically around the comma stage during embryonic development to control a left/right asymmetric differentiation program in the C. elegans nervous system. This suggests that a transient input of
lsy-6 during development is sufficient to specify the neuronal cell fate.
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[
FEMS Microbiol Lett,
2014]
Staphylococcus lugdunensis is a human skin commensal organism, but it is considered as a virulent Staphylococcus species. In a previous study, we described the first S.lugdunensis autolysin, AtlL. This enzyme displays two enzymatic domains and generates two peptidoglycan hydrolases, an N-acetylmuramoyl-l-alanine amidase and an N-acetylglucosaminidase. In this study, to further investigate the functions of this autolysin, a atlL mutant was constructed. The microscopic examination of the mutant showed cell aggregates and revealed a rough outer cell surface demonstrating, respectively, the roles of AtlL in cell separation and peptidoglycan turnover. This atlL mutant exhibited a lower susceptibility to Triton X-100-induced autolysis assays and appears to be more resistant to cell wall antibiotic-induced lysis and death compared with its parental strain. The atlL mutation affected the biofilm formation capacity of S.lugdunensis. Furthermore, the atlL mutant showed trends toward reduced virulence using the Caenorhabditis elegans model. Overall, AtlL appears as a major cell wall autolysin of S.lugdunensis implicated in cell separation, in stress-induced autolysis and in bacterial pathogenesis.
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[
Trends Microbiol,
1999]
As outlined by Michal Jazwinski in his recent review, multiple pathways appear to play a role in determining yeast longevity. One mechanism involves the illegitimate replication of extrachromosomal rDNA circles to toxic levels. A similar sequence of events involving excision, circularization and unfettered replication of mitochondrial (mt) DNA (called senDNA) induces senescence in the fungus Podospora anserina.
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[
Biophys Chem,
2005]
Lifespan regulation through gene expression involves complex biochemical processes. Unfortunately, current mathematical models for treating lifespan data afford little insight into the mechanisms that control longevity. In this work, we demonstrate the use of a novel kinetic model to successfully fit the lifespan curves of the nematode, Caenorhabditis elegans. Our findings show that population aging may be treated analogously to a dispersive chemical process [P.J. Skrdla, R.T. Robertson., J. Phys. Chem. B 109 10611 (2005)]. Much like the Gompertz model, only two fit parameters, alpha and beta, are needed to adequately describe the entire data set for each nematode population. These parameters relate a ''global first-order time constant'' and a ''global second-order rate constant'', with units of (time) and (time)(-2), respectively. In C. elegans, the increased longevity resulting from DAF-16 (a transcription factor) activity in the intestinal tissue correlates with a larger alpha value and a smaller beta value; the opposite is true for animals with shorter lifespans. A basic physical interpretation of the two parameters is provided.