Rougvie, Ann E. et al. (2009) International Worm Meeting "Caenorhabditis Genetics Center."

Stiernagle, Theresa, Rougvie, Ann E.

[International Worm Meeting, 2009]

The Caenorhabditis Genetics Center (CGC), supported by the National Institutes of Health - National Center for Research Resources (NIH-NCRR), supplies Caenorhabditis strains and information to researchers throughout the world. The CGC continues to be housed at the University of Minnesota, but will see changes in the next year as Theresa Stiernagle retires as Curator and pursues other interests. The CGC will continue its duties of acquiring, maintaining and distributing worm stocks. The CGC now has over 11,499 different strains. We strive to have at least one allele of every published gene and all chromosome rearrangements, duplications and deficiencies. Selected multiple-mutant stocks and transgenic strains are also available including strains that express various green fluorescent protein (GFP) reporter fusions. The CGC also has stocks of nematode species closely related to C. elegans and bacterial strains necessary for nematode growth. A searchable strains list, including information about CGC stocks, is accessible either through the CGC website (www.cbs.umn.edu/CGC/) or through WormBase. Requests for strains should be made via the on-line ordering system available through our website. As mandated by NIH-NCRR, a small yearly user fee and charge per strain is assessed with each order. The CGC strongly encourages use of credit cards for these charges. We provide quarterly reports to the NIH with statistics that reflect our services to the worm community. We especially like to be acknowledged in papers for providing strains. We also like to receive pdf files of such papers, copies of which we provide to NIH.

Saiki R et al. (2008) Aging Cell "Altered bacterial metabolism, not coenzyme Q content, is responsible for the lifespan extension in Caenorhabditis elegans fed an Escherichia coli diet lacking coenzyme Q."

Saiki R, Clarke CF, Furukawa S, Larsen PL, Bixler T, Lunceford AL, Lee W, Dang P

[Aging Cell, 2008]

Coenzyme Qn is a fully substituted benzoquinone containing a polyisoprene tail of distinct numbers (n) of isoprene groups. C. elegans fed E. coli devoid of Q(8) have a significant life span extension when compared to C. elegans fed a standard "Q-replete"E. coli diet. Here we examine possible mechanisms for the life span extension caused by the Q-less E. coli diet. A bioassay for Q uptake shows that a water-soluble formulation of Q(10) is effectively taken up by both clk-1 mutant and wild-type nematodes, but does not reverse life span extension mediated by the Q-less E. coli diet, indicating that life span extension is not due to the absence of dietary Q per se. The enhanced longevity mediated by the Q-less E. coli diet cannot be attributed to dietary restriction, different Qn isoforms, reduced pathogenesis or slowed growth of the Q-less E. coli, and in fact requires E. coli viability. Q-less E. coli have defects in respiratory metabolism. C. elegans fed Q-replete E. coli mutants with similarly impaired respiratory metabolism due to defects in complex V also show a pronounced life span extension, although not as dramatic as those fed the respiratory deficient Q-less E. coli diet. The data suggest that feeding respiratory incompetent E. coli, whether Q-less or Q-replete, produces a robust life extension in wild-type C. elegans. We believe the fermentation-based metabolism of the E. coli diet is an important parameter of C. elegans longevity.

Bartolini F et al. (2005) J Cell Sci "Identification of a novel tubulin-destabilizing protein related to the chaperone cofactor E."

Cassimeris L, Tian G, Piehl M, Bartolini F, Cowan NJ, Lewis SA

[J Cell Sci, 2005]

Factors that regulate the microtubule cytoskeleton are critical in determining cell behavior. Here we describe the function of a novel protein that we term E-like based on its sequence similarity to the tubulin-specific chaperone cofactor E. We find that upon overexpression, E-like depolymerizes microtubules by committing tubulin to proteosomal degradation. Our data suggest that this function is direct and is based on the ability of E-like to disrupt the tubulin heterodimer in vitro. Suppression of E-like expression results in an increase in the number of stable microtubules and a tight clustering of endocellular membranes around the microtubule-organizing center, while the properties of dynamic microtubules are unaffected. These observations define E-like as a novel regulator of tubulin stability, and provide a link between tubulin turnover and vesicle transport.

BC Prasad et al. (1999) International C. elegans Meeting "The unc-3 locus encodes an O/E transcription factor, CeO/E, which is required for axonal guidance and chemosensory function."

BC Prasad, RR Reed

[International C. elegans Meeting, 1999]

The O/E family of rHLH transcription factors has been implicated in neurogenesis, axonal pathfinding, muscle formation and B cell maturation. The murine O/E proteins are expressed transiently in the developing CNS and PNS during times of axonogenesis and are expressed in olfactory neurons throughout development where they may regulate components of the olfactory signaling cascade. We have identified a C. elegans O/E homologue (CeO/E) that is encoded by the unc-3 locus. Unc-3 mutants display an uncoordinated phenotype attributed to a severe defasiculation and miswiring of the ventral cord (VNC). Using a GFP fusion to the unc-3 promoter and specific antibodies, we observed that CeO/E is expressed transiently in the excitatory VNC motor neurons and throughout development in a pair of chemosensory neurons (ASI amphid neurons). Several observations suggest that the protein may have distinct roles in the two cell types. Although the axonal and dendritic projections of the ASI appear to be normal when labeled with DiI, unc-3 mutants enter the dauer pathway under inappropriate conditions. Although CeO/E possesses highly conserved domains associated with DNA binding in the mammalian homologue, identification of DNA binding sites for the C. elegans protein has not been achieved. We have shown that CeO/E protein can homodimerize in vitro, although the DNA binding specificity of CeO/E is distinct from the mammalian O/E proteins. Several unc-3 target genes ( daf-7, unc-17/cha-1, unc-4 ) have been identified by other laboratories and each contains a mammalian binding site in the promoter region. Remarkably, we have been unable to demonstrate CeO/E binding at these sites. We are generating chimeras of O/E-1 and CeO/E to understand the DNA binding specificity of the CeO/E protein and utilizing a yeast-2-hybrid screen with both O/E-1 and CeO/E to identify interacting proteins in C. elegans . These studies should reveal the mechanism of CeO/E transcriptional activation and target gene regulation.

Garsin DA et al. (2001) Proc Natl Acad Sci U S A "A simple model host for identifying Gram-positive virulence factors."

Mylonakis E, Ausubel FM, Singh KV, Sifri CD, Calderwood SB, Murray BE, Qin X, Garsin DA

[Proc Natl Acad Sci U S A, 2001]

We demonstrate the use of the nematode Caenorhabditis elegans as a facile and inexpensive model host for several Gram-positive human bacterial pathogens. Enterococcus faecalis, Streptococcus pneumoniae, and Staphylococcus aureus, but not Bacillus subtilis, Enterococcus faecium, or Streptococcus pyogenes, kill adult C elegans. Focusing our studies on the enterococcal species, we found that both E. faecalis and E. faecium kill C elegans eggs and hatchlings, although only E. faecalis kills the adults. In the case of adults, a low inoculum of E, faecalis grows to a high titer in the C elegans intestine, resulting in a persistent infection that cannot be eradicated by prolonged feeding on E. faecium. Interestingly, a high titer of E. faecium also accumulates in the nematode gut, but does not affect the longevity of the worms. Two E. faecalis virulence-related factors that play an important role in mammalian models of infection, tsr, a putative quorum-sensing system, and cytolysin, are also important for nematode killing. We exploit the apparent parallels between Gram-positive infection in simple and more complex organisms by using the nematode to identify an E. faecalis virulence factor, ScrB, which is relevant to mammalian pathogenesis.

Resnick T D et al. (2010) Aging, Metabolism, Stress, Pathogenesis, and Small RNAs, Madison, WI "Regulation and Function of the let-7-related miRNA miR-48 in Developmental Timing"

Rougvie A E, Resnick T D, Edelman T B

[Aging, Metabolism, Stress, Pathogenesis, and Small RNAs, Madison, WI, 2010]

The heterochronic genes of C. elegans regulate temporal development, ensuring that developmental events proceed in correct sequence and at appropriate times. These genes, along with spatial and sexual regulators, are essential for proper patterning of the adult animal and include the first-identified miRNA genes, lin-4 and let-7. Loss of function of these miRNAs leads to reiteration of certain developmental events and delay of adult tissue differentiation, referred to as a ""retarded"" phenotype. let-7 miRNA shares identity at its 5' end with several other miRNAs including miR-48, miR-241, and miR-84, suggesting that they may target an overlapping set of mRNAs. These let-7-related miRNAs are expressed earlier in development than is let-7. Individual deletion of these genes results in only mild defects, however a triple deletion leads to a strong retarded phenotype, indicating that these miRNAs function redundantly. Early and elevated expression of mir-48, either by regulatory alleles or by over-expression from multicopy transgenic arrays, leads to ""precocious"" phenotypes in which certain developmental patterns are skipped and subsequent events occur too early. We have taken advantage of the heterochronic gene pathway as a robust model for understanding regulation of miRNA expression and function, the relationships of related miRNAs, and the roles of miRNAs within gene regulatory networks. To identify additional genes involved in developmental timing and miRNA expression or function, we screened for suppressors of mir-48 over-expression. We isolated 36 suppressed lines from 48,000 haploid genomes screened. Preliminary analysis indicates some of the suppressor alleles on their own result in retarded phenotypes, validating this approach for identification of new heterochronic genes. In a parallel approach to target mir-48 transcriptional regulators directly, we are examining candidate genes to determine their effects on mir-48 expression and developmental timing in vivo.

He Y et al. (2023) Cell Rep "N-glycosylated intestinal protein BCF-1 shapes microbial colonization by binding bacteria via its fimbrial protein."

Tian G, Zhang Y, Fu K, Qi B, Fu H, He Y, Hao F

[Cell Rep, 2023]

Microbial colonization plays an instrumental role in the health of the host. However, the host factors that facilitate the establishment of the microbial colonization remain unclear. Here, we establish a screening method to identify host factors regulating E. coli colonization in C. elegans. We find that a BCF-1 possessing N-glycosylation promotes E. coli colonization by directly binding to E. coli via its fimbrial protein, YdeR. BCF-1 is activated by the bacteria and interacts with an oligosaccharyl transferase, OSTB-1, which is critical for regulating E. coli colonization. We also show that the N-glycosylation of BCF-1 is critical for E. coli colonization. In addition, we find that the microbiota composition is shaped by BCF-1. In summary, this study shows a "scaffold model" for bacterial colonization between a host glycoprotein and E. coli, and it also introduces a powerful research approach to identify individual host factors involved in modulating bacterial colonization.

Shaulov Y et al. (2018) PLoS Pathog "Escherichia coli mediated resistance of Entamoeba histolytica to oxidative stress is triggered by oxaloacetate."

Shaulov Y, Lamm AT, Ankri S, Trebicz-Geffen M, Weiss-Cerem L, Hisaeda H, Methling K, Lalk M, Nagaraja S, Shimokawa C

[PLoS Pathog, 2018]

Amebiasis, a global intestinal parasitic disease, is due to Entamoeba histolytica. This parasite, which feeds on bacteria in the large intestine of its human host, can trigger a strong inflammatory response upon invasion of the colonic mucosa. Whereas information about the mechanisms which are used by the parasite to cope with oxidative and nitrosative stresses during infection is available, knowledge about the contribution of bacteria to these mechanisms is lacking. In a recent study, we demonstrated that enteropathogenic Escherichia coli O55 protects E. histolytica against oxidative stress. Resin-assisted capture (RAC) of oxidized (OX) proteins coupled to mass spectrometry (OX-RAC) was used to investigate the oxidation status of cysteine residues in proteins present in E. histolytica trophozoites incubated with live or heat-killed E. coli O55 and then exposed to H2O2-mediated oxidative stress. We found that the redox proteome of E. histolytica exposed to heat-killed E. coli O55 is enriched with proteins involved in redox homeostasis, lipid metabolism, small molecule metabolism, carbohydrate derivative metabolism, and organonitrogen compound biosynthesis. In contrast, we found that proteins associated with redox homeostasis were the only OX-proteins that were enriched in E. histolytica trophozoites which were incubated with live E. coli O55. These data indicate that E. coli has a profound impact on the redox proteome of E. histolytica. Unexpectedly, some E. coli proteins were also co-identified with E. histolytica proteins by OX-RAC. We demonstrated that one of these proteins, E. coli malate dehydrogenase (EcMDH) and its product, oxaloacetate, are key elements of E. coli-mediated resistance of E. histolytica to oxidative stress and that oxaloacetate helps the parasite survive in the large intestine. We also provide evidence that the protective effect of oxaloacetate against oxidative stress extends to Caenorhabditis elegans.

Kaushal NA et al. (1982) J Immunol "Identification and characterization of excretory-secretory products of Brugia malayi, adult filarial parasites."

Kaushal NA, Ottesen EA, Nash TE, Hussain R

[J Immunol, 1982]

Although E-S antigens may be particularly important for both the pathogenesis and immunodiagnosis of helminth infections, little is known about the immunochemistry or functional roles in human filarial infections. In the present paper, we have done some initial identification and characterization of E-S products of adult Brugia malayi by employing a combination of sensitive biochemical and immunochemical techniques. E-S products, collected by incubating B. malayi adults in vitro in a defined protein-free medium, were radiolabeled with 125I. SDS-polyacrylamide gel electrophoresis (PAGE) and autoradiography of labeled E-S products revealed 11 protein bands in the m.w. range of 10,000 to 70,000. Comparison of radiolabeled E-S products and adult somatic antigen (B.m.A) in SDS-PAGE indicated many common bands, and crossed immunoelectrophoresis and competitive Staph-A RIA confirmed the presence of most E-S antigens in B.m.A. Of the 11 E-S bands, two appeared to be derived from the surface of the adult worms and microfilariae as shown by SDS-PAGE and autoradiography of lodogen surface-labeled parasites; the presence of two host proteins in E-S was detected by crossed-line immunoelectrophoresis. The E-S antigens were highly immunogenic when tested both with rabbit antiserum raised against B.m.A and with a serum pool of patients with natural filarial infection.

Choi H et al. (2017) Dev Biol "Partially compromised specification causes stochastic effects on gut development in C. elegans."

Broitman-Maduro G, Maduro MF, Choi H

[Dev Biol, 2017]

The C. elegans gut descends from the E progenitor cell through a series of stereotyped cell divisions and morphogenetic events. Effects of perturbations of upstream cell specification on downstream organogenesis have not been extensively investigated. Here we have assembled an allelic series of strains that variably compromise specification of E by perturbing the activation of the gut-specifying end-1 and end-3 genes. Using a marker that allows identification of all E descendants regardless of fate, superimposed with markers that identify cells that have adopted a gut fate, we have examined the fate of E lineage descendants among hundreds of embryos. We find that when specification is partially compromised, the E lineage undergoes hyperplasia accompanied by stochastic and variable specification of gut fate among the E descendants. As anticipated by prior work, the activation of the gut differentiation factor elt-2 becomes delayed in these strains, although ultimate protein levels of a translational ELT-2::GFP reporter resemble those of the wild type. By comparing these effects among the various specification mutants, we find that the stronger the defect in specification (i.e. the fewer number of embryos specifying gut), the stronger the defects in the E lineage and delay in activation of elt-2. Despite the changes in the E lineage in these strains, we find that supernumerary E descendants that adopt a gut fate are accommodated into a relatively normal-looking intestine. Hence, upstream perturbation of specification dramatically affects the E lineage, but as long as sufficient descendants adopt a gut fate, organogenesis overcomes these effects to form a relatively normal intestine.