P Bauer et al. (2001) International C. elegans Meeting "Sins and saps: investigating components of the Caenorhabditis elegans Sin3-histone deacetylase complex."

A Mounsey, P Bauer, I A Hope

[International C. elegans Meeting, 2001]

The significance of histone acetylation and deacetylation in transcriptional regulation has only been realised within the last five years. Hyperacetylation of lysine residues in histone tails correlates to up regulation of transcription and, conversely, hypoacetylation correlates to down regulation of transcription. Removal of some acetyl groups by deacetylase enzymes, is mediated by a Sin3-containing protein complex. Sin3 interacts with many transcriptional repressor proteins directly (such as MNF- b and MAD), or indirectly through N-CoR and SMRT. The Sin3-deacetylase complex is evolutionarily conserved and has been found in organisms ranging from yeast to mouse to human. The following members of this complex: sin3 , sap18 and sap30 have been identified in C. elegans by analysis of the complete genome sequence. We have investigated the function of these components by both the construction of reporter gene fusions, and through examination of phenotypes generated by double-stranded RNA interference (RNAi). Ce-sin3::gfp begins expressing in embryos around the 8 E-cell stage, and through to adulthood in head and tail ganglia, the ventral nerve cord, intestine, hypodermis, pharynx and somatic gonad. RNAi for this gene affects the egg-laying rate of F1 progeny. Ce- s ap18 ::gfp shows extensive expression in embryos, becoming restricted to the head in early larvae. Some expression is also observed in adult heads. No phenotype was observed from RNAi experiments targeted to this gene. The putative Ce-sap30 when fused to GFP, is solely expressed in the excretory cell and canals, however when crossed with N2 males some expression has been seen in pre-elongated embryos. The RNAi phenotype for this gene is a highly penetrant embryonic lethal.

Bauer G et al. (1991) International C. elegans Meeting "THE MOLECULAR ANALYSIS OF A SUPPRESSOR FOR AN ORGAN-SPECIFIC DIFFERENTIATION GENE OF CAENORHABDITIS ELEGANS"

Schnabel R, Schnabel H, Granato M, Bauer G

[International C. elegans Meeting, 1991]

We are studying pha-l, a zygotic embryonic lethal gene required for pharyngeal differentiation and morphogenesis. In order to find interacting genes we isolated revertants of the temperature sensitive alleles of pha-l ( e2123 and tlOOI). Exposing the progeny of mutagenized animals to the non-permissive temperature, a large number of pha-l revertants were isolated. After mutagenesis with EMS we isolated 178, with X-rays 24 suppressor mutations. Using the C. elegans mutator strains TR679 and TR403 with increased frequency of transposition of the transposon TCl, 8 mutations were isolated. Also 10 spontaneous mutations were found. These 220 mutations fall into three different complementation groups that map on LGIII ( sup-35 ), on LGIV ( sup-36 ) and on LGV (sup-37). All the mutations in the three different suppressor genes are recessive. sup-36 and sup-37 are strictly zygotic whereas sup-35 can be expressed either maternally or zygotically. Except for suppression of pha-l no other phenotype associated with the three suppressors could be found. sup-35 is defined by 176 alleles and maps 0.1 MU to the left of pha-l. The pha-l region is covered with overlapping DNA clones and a detailed restriction map has been worked out. Genomic Southern hybridisation analysis of sup-35 alleles revealed different polymorphisms, e.g. deletions in at least 14 mutations. In Northern hybridisation experiments we could identify a 2.0 kb transcript in wildtype embryos that is missing in sup-35 ( tl 014 and tl 013 J. In order to understand the cellular function and mechanism of suppression of sup- 35 we are cloning and sequencing this gene. Microinjection of cloned suppressor DNA into the suppressed strain should restore the pha-l phenotype which would provide definite proof of having cloned the suppressor gene.

Bauer PK et al. (1997) International C. elegans Meeting "EXPRESSION PATTERN SCREEN FOR GENES PREDICTED IN THE C. elegans GENOME SEQUENCING PROJECT - AN UPDATE."

Bauer PK, Mounsey A, Royall CM, Hope IA, Lynch AS

[International C. elegans Meeting, 1997]

Dennis RD et al. (2011) Parasitology "Angiogenesis and parasitic helminth-associated neovascularization."

Schubert U, Bauer C, Dennis RD

[Parasitology, 2011]

Successful metazoan parasitism, among many other factors, requires a supply of nutrients and the removal of waste products. There is a prerequisite for a parasite-defined vasculature. The angiogenic mechanism(s) involved presumably depend on the characteristics of the tissue- and vascular system-dwelling, parasitic helminths. Simplistically, 2 possibilities or a combination of both have been considered in this review. The multifactorial induction of parasitic helminth-associated neovascularization could arise through, either a host-, a parasite- or a host-/parasite-dependent, angiogenic switch. Most studies appear to support the first and third hypotheses, but evidence exists for the intrahepatic cestode Echinococcus multilocularis, the free-living nematode Caenorhabditis elegans and the intravascular trematode Schistosoma mansoni for the second inference. In contrast, the nematode anti-coagulant protein NAPc2 from adult Ancylostoma caninum is also an anti-angiogenic factor.

Bauer CC et al. (1995) Worm Breeder's Gazette "Myotonic Dystrophy Homologs in C. elegans?"

Fleming S, Epstein HF, Bauer CC

[Worm Breeder's Gazette, 1995]

We are interested in determining the possible use of C. elegans as an animal model to study the protein(s) indicated in the human disease Myotonic Dystrophy, (DM). We therefore performed a computer search of the dbEST database to locate cDNAs that were similar in sequence to the DM protein kinase gene, (DMPK). We found four different sequences with protein sequence similarities ranging from 50 to 95% over the short regions that had been sequenced. One cDNA (Accession # T01329) in the databases was originally found by Anthony Kerlavage at the Institute for Genomic Research in Gaithersburg, MD. The clone, CEESP52, came from a C. elegans embryonic cDNA library. One open-reading frame of the clone contained a protein sequence that matches at a score of 71% identity and 95% similarity to part of the catalytic domain of the human DM kinase gene. We have hybridized a probe made from CEESP52 to the Yac contig library and determined that the gene containing the coding sequences is found on Yac Y38B5. Yac Y38B5 is covered by known cosmids except for an approximately 20kb gap in the cosmid contigs. A Southern indicated that the region sequenced did not hybridize to any of the cosmids, therefore we believe that at least part, if not all, of the gene is located in the gap region. We have run pulse field gels and isolated Yac Y38B5 DNA and will be screening subclones of the Yac for the corresponding gene. We will then perform rescue experiments of known mutations or construct our own mutant. As another approach to locating DMPK homologs we have used is employing a monoclonal and polyclonal antibodies made to the human DMPK protein on Western blots containing C. elegans homogenates. The monoclonal antibody identified an approximately 80kDa band on the Western, whereas the polyclonal detected 5 different bands. We are in the process of isolating these genes from a lgt11 embryonic library. Below is a translated protein sequence match of the 4 closest homologs to DMPK found in the dbEST database over a overlapping 100 amino acid region. Two other cDNA sequences in the dbEST database have good similarity scores to DMPK equivalent to the C. elegans Ndr peptide score, but are not in the same region. Both have been mapped and are found on chromosome I (1,2). The partial sequence of the Ndr protein has been recently published and has homologs in both Drosophila and humans (3). .................................................................. Upper Sequence Human DMPK (all matches to the Human DMPK) . 2nd Sequence Accession # T01329 peptide Match Percentage 71% 3rd Sequence C. elegans Ndr peptide Match Percentage 45% 4th Sequence Accession # D37290 peptide Match Percentage 35% . . . : . : . : . : 1 DFEILKVIGRGAFSEVAVVKMKQTGQVYAMKIMNKWDMLKRGEVSCFREE |||:|||||:|||:|||||:|: |::|||||:|||:|:||:|||||| 1 DFEVLKVIGKGAFGEVAVVRMRGVGEIYAMKILNKWEMVKRAETACFREE :| |||||||||:|||: :||::|||||: | :|: : : : | | 1 HFKSLKVIGRGAFGEVRLVQKHDTGHIYAMKILRKSEMVEKEQTAHVRAE :||:|:|:||: :| :|: | :||||:: | :| : : | 1 NFALLRVLGKGAYGKVFLVRKDHNTIYAMKVLRKTRVLTKQKXLEHTMAE . . . : . : . : . 51 RDVLVNGDRRWITQLHFAFQDENYLYLVMEYYVGGDLLTLLSKFGERIP ||||| |||||||:||:|||||: ||:||:||:|||:|||||||:|| 51 RDVLVYGDRRWITNLHYAFQDEKNLYFVMDYYIGGDMLTLLSKFVDHIP ||:|:| |: :: ::||| : ||||||: |||::||| | : 51 RDILSEADCDWVVKMYYSFQDYSNLYLVMEFLPGGDMMTLLIKKATLTE | ||: | :||| : |::|||| ||:| | | | 51 RQVLERLRTPFLVNLXYAFQTDXKLHIVMEYVRGGELFTHLCSRGH .................................................................. 1) Gilchrist, E. and Baillie, D., (1995) A C. elegans Myotonic Dystrophy gene homologue. Abstracts of the 10th International C. Elegans meeting. University of Wisconsin, Madison. P233. 2) Wissmann, A., McGhee, J., Mains, P., (1995) Let-502 is a homolog of human Myotonic Dystrophy kinase. Abstractions of the 10th International C. elegans meeting. University of Wisconsin, Madison. P548. 3) Millward, T., Cron, P., Hemmings, B., (1995) Molecular cloning and characterization of a conserved nuclear serine(threonine) protein kinase. Proc. Natl .Acad. Sci. USA 92:5022-6.

Bauer, R. et al. (2019) International Worm Meeting "Modeling Long-QT Syndrome in C. elegans."

Golden, A., Bauer, R.

[International Worm Meeting, 2019]

Rare diseases, which together affect about 1 in 10 Americans, are largely understudied due to barriers in funding, awareness, and sample size. Around 80% of rare diseases are monogenic, and many affected genes have orthologs in C. elegans. CRISPR/Cas9 technology allows us to create precise worm models of human disease alleles. The ability to look for interactors, pathways, and suppressors in worms increases the body of knowledge about the human diseases. Here we demonstrate that C. elegans are an appropriate model system for a rare autosomal dominant cardiac arrhythmia, Long-QT Syndrome 1 (LQTS1), caused by mutations in the voltage-gated potassium channel gene KCNQ1 in humans and kqt-3 in worms.

Bauer J et al. (2021) Development "The initial expansion of the C. elegans syncytial germ line is coupled to primordial germ cell cytokinesis incompletion."

Goupil E, Nguyen KCQ, Bauer J, Hall DH, Labbe JC, Poupart V

[Development, 2021]

The C. elegans germline is organized as a syncytium in which each germ cell possesses an intercellular bridge that is maintained by a stable actomyosin ring and that connects it to a common pool of cytoplasm, termed the rachis. How germ cells undergo cytokinesis while maintaining this syncytial architecture is not completely understood. Here we use live imaging to characterize primordial germ cell (PGC) division in C. elegans first-stage larvae. We show that each PGC possesses a stable intercellular bridge that connects it to a common pool of cytoplasm, which we term the proto-rachis. We further show that the first PGC cytokinesis is incomplete and that the stabilized cytokinetic ring progressively moves toward the proto-rachis and eventually integrates into it. Our results support a model in which the initial expansion of the C. elegans syncytial germline occurs by incomplete cytokinesis, where one daughter germ cell inherits the actomyosin ring that was newly formed by stabilization of the cytokinetic ring, while the other inherits the pre-existing stable actomyosin ring. We propose that such a mechanism of iterative cytokinesis incompletion underpins C. elegans germline expansion and maintenance.

Weinstein EJ et al. (2003) Biochim Biophys Acta "URP1: a member of a novel family of PH and FERM domain-containing membrane-associated proteins is significantly over-expressed in lung and colon carcinomas."

Weinstein EJ, Zakeri H, Bourner M, Head R, Mazzarella R, Bauer C

[Biochim Biophys Acta, 2003]

In a concerted effort to identify biomarkers for lung and colon carcinomas by genome-wide transcriptional profiling, we describe the identification and cloning of one such gene as well as two additional closely related genes. Due to the strong sequence homology to the C. elegans UNC-112 we call this gene URP1, for UNC-112 related protein. We have also isolated the full-length clones for another novel related gene, URP2 and the previously discovered MIG-2 gene. Collectively, these proteins, together with two from Drosophila, appear to form a novel membrane-associated FERM and PH domain-containing protein family. Transcriptional analysis shows that only URP1 is significantly differentially regulated, being over-expressed in 70% of the colon carcinomas and 60% of the lung carcinomas tested. Quantification of URP1 expression by qRT-PCR showed up-regulation of the gene by 60-fold in lung tumors and up to nearly 6-fold in colon tumors. Northern blot analysis of URP1 indicates that normal expression is restricted to neuromuscular tissues. In contrast, the expression of URP2 appears to be confined primarily to tissues of the immune system. SNP analysis of URP1 reveals that it is highly polymorphic, containing seven sites, four of which are in the coding region and one position that results in the interchangeable substitution of glutamic acid and lysine. Finally, we have shown that the genomic structure for all three genes is nearly identical with all encoded by 15 exons although URP1 gene localized to chromosome 20p13, URP2 to 11q12 and MIG-2 to 14q22. This conserved exon structure suggests that all three members probably arose by gene duplication from one ancestral gene. The presence of multiple FERM domains characteristic of cytoplasmic plasma membrane to cytoskeleton linkers and a PH domain typical of membrane-anchored proteins involved in signal transduction suggest an important role for URP1 in tumorigenesis.

Coles GC et al. (1992) Vet Parasitol "World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance."

Waller PJ, Bauer C, Klei TR, Coles GC, Borgsteede FH, Geerts S, Taylor MA

[Vet Parasitol, 1992]

Methods have been described to assist in the detection of anthelmintic resistance in strongylid nematodes of ruminants, horses and pigs. Two tests are recommended, an in vivo test, the faecal egg count reduction test for use in infected animals, and an in vitro test, the egg hatch test for detection of benzimidazole resistance in nematodes that hatch shortly after embryonation. Anaerobic storage for submission of faecal samples from the field for use in the in vitro test is of value and the procedure is described. The tests should enable comparable data to be obtained in surveys in all parts of the world.

Yao H et al. (2022) Front Pharmacol "Evaluation of in vivo antibacterial drug efficacy using Caenorhabditis elegans infected with carbapenem-resistant Klebsiella pneumoniae as a model host"

Liu J, Yao H, Chen J, Wang F, Xu A

[Front Pharmacol, 2022]

Objective: This study was developed to assess the in vivo antimicrobial activity of specific drugs using a model system consisting of Caenorhabditis elegans (C. elegans) infected with Carbapenem-resistant Klebsiella pneumoniae (CRKP) in an effort to identify promising drugs for CRKP-infected patient treatment. Methods: A C. elegans-CRKP liquid assay platform was developed and used to conduct limited in vivo screening for antimicrobial agents with potential activity against CRKP. Time curves for 10 different concentrations of tested antimicrobial agents were tested in this model system at 0, 2, 6, 8, and 12 h after treatment. The protective effects of these different antimicrobial agents were compared at different time points. Furthermore, ten CRKP strains samples were isolated from clinical specimens to demonstrate the applicability of the nematode model method, and two typical clinical cases are presented. Results: CRKP bacteria were sufficient to induce C. elegans death in a dose- and time-dependent fashion, while effective antimicrobial agents improved the survival of these nematodes in a dose-dependent manner. Notably, PB and TGC exhibited robust antibacterial protection within 12 h even at low tested concentrations, and clear efficacy remained evident for high doses of CAZ at this same time point as mediators of improved nematode survival. The results of C. elegans model method were well consistent with that using the Kirby-Bauer method in 10 CRKP strains samples, and two typical clinical cases showed applicability, reliability and efficacy of C. elegans model method. Conclusion: Overall, nematode models in drug sensitivity testing have shown advantages in clinical settings. Our results highlight the value of C. elegans model systems as tools for the simultaneous screening of different agents for in vivo antibacterial efficacy and are deserved further study.