Goldberg, Hailey V. et al. (2019) International Worm Meeting "Development of a UGT Mutant Library in Caenorhabditis elegans."

Edison, Arthur S., Asif, Muhammad Z., Doll, Jack, Roth, Julia, Goldberg, Hailey V.

[International Worm Meeting, 2019]

The purpose of this study is to create a Caenorhabditis elegans (C. elegans) mutant library by using CRISPR/Cas9 to knock out UGT genes. This library will be comprised of the existing UGT mutants in order to provide us with the needed information to peruse other non-explored UGT genes to knock out in the future. In C. elegans, UGT genes regulate the glycosylation of environmental toxins allowing for survival of the nematode[1]. CRISPR/Cas9 is a powerful gene-editing system allowing for a Cas9 endonuclease to induce a double strand break in the DNA, rendering non-homologous end joining between the broken DNA[2]. As a result, that particular gene in the DNA is knocked out and a mutant is created. As part of the Vertically Integrated Projects (VIP) undergraduate research team at UGA, we have developed a workflow that will allow us to create this mutant library[3]. Upon completion, this library will allow us to test the effects of different xenobiotics and natural compounds on UGT knockout mutants which will allow us to better understand the role of these genes and their associated proteins in the glycosylation and drug resistance pathways of C. elegans; this provides us with a model which can be later be tested in parasitic nematodes. Additionally, the CRISPR/Cas9 protocols established for UGT knockouts will allow future undergraduate students to partake in CRISPR/Cas9 genetic research through the VIP program in the Edison Lab to continue producing UGT mutants for metabolomics analysis.

Ben Lehner et al. (2006) European Worm Meeting "Systematic Mapping of Genetic Interactions in C. elegans Suggests a New Paradigm for Human Genetic Disease"

Catriona Crombie, Andrew G. Fraser, Ben Lehner, Angelo Fortunato, Julia Tischler

[European Worm Meeting, 2006]

Ben Lehner, Catriona Crombie, Julia Tischler, Angelo Fortunato and Andrew G. Fraser Most heritable traits, including disease susceptibility, are affected by the interactions between multiple genes. However, we still understand very little about how genes interact since only a minute fraction of possible genetic interactions have been explored experimentally. To begin to address this, we are using RNA interference to identify genetic interactions in C. elegans, focussing on genes in signalling pathways that are mutated in human diseases. We tested ~65,000 pairs of genes for possible interactions and identify ~350 genetic interactions. This is the first systematically constructed genetic interaction map for any animal. We successfully rediscover most components of previously known signalling pathways; furthermore, we verify 9 novel modulators of EGF signalling. Crucially, our dataset also provides the first insight into the global structure of animal genetic interaction maps. Most strikingly, we identify a class of highly connected ''hub'' genes: inactivation of these genes greatly enhances phenotypes resulting from mutations in many different pathways. These hub genes all encode chromatin regulators, and their activity as genetic hubs appears conserved across metazoans. We propose that these genes function as general buffers of genetic variation and that these hub genes will act as modifier genes in multiple, mechanistically unrelated genetic diseases in humans.

Waring DA et al. (1995) International C. elegans Meeting "Identification of a New bHLH Gene That May Play a Role In C. elegans Neurogenesis."

Waring DA, Weintraub H

[International C. elegans Meeting, 1995]

The bHLH gene neuroD was first identified in the mouse using a two-hybrid screen. The expression pattern of neuroD in the mouse and the frog suggests that it may be important for specification of neurons. In addition overexpression of neuroD in frog embryos leads to the production of ectopic neurons, apparently at the expense of epidermal cells (Lee et al. Science in Press). neuroD defines a new family of bHLH genes that is distinct from the achaete-scute family. A search of the sequence database identified a C. elegans homologue of neuroD on chromosome 3 that had been sequenced by the Genome Project which we are tentatively calling cnd-1. We have begun a study of this gene with the thought that it may prove to be important for neural development. We have made use of the three "Cubes" prepared by the Roth and Priess labs and have identified two insertions into the cnd-1 gene. Neither of these insertions have an obvious phenotype. One of these genes is in an intron while the other is 3' to the coding region. We have not determined if it is in a transcribed region. Presently we are sequencing cDNAs and preparing to do in-situ, hybridization studies, as well as attempting to generate a knock-out of the gene by imprecise excision of the TC1 insertions.

Bo Wang et al. (2006) European Worm Meeting "Multi-Parameter Axial Profiling of Transgenic C. elegans Expressing Fluorescent Proteins from Various Cell-Specific, Tissue Specific and Developmentally Regulated Promoters"

Bruce Holcombe, Julia Thompson, Yanping Zhang, Rock Pulak, Bo Wang, Michael Herman, Mariya Lomakina

[European Worm Meeting, 2006]

Bo Wang1, Julia Thompson1, Yanping Zhang2, Michael Herman2, Mariya Lomakina1, Bruce Holcombe1, Rock Pulak1 . The COPAS Biosort instrument automates the analysis, sorting, and dispensing of all stages of C. elegans, measuring the animals size and the intensity of expressed fluorescent markers. Once analyzed, animals can be selected according to user defined criteria, and then dispensed into multi-well plates for high throughput screening or collected in bulk for further analysis. With this technology, time required for large scale screening for certain changes in the optical properties of the animals, such as changes in the levels of expression of a fluorescent protein, can be dramatically reduced and human error minimized. Recent enhancements to an add-on module, called the Profiler II, have been tested for its ability to collect positional information of fluorescent expression. The instrument can simultaneously collect fluorescence information in three separate regions of the spectrum. Here we show that the instrument can analyze multi-colored transgenic animals and can be used to compare the amounts and relative positions of expression of two or three different colors of fluorescence. Furthermore, this technology can be used to screen for independent changes in the intensity or position of each reporter protein. We have tested various transgenic animals expressing green, yellow and/or red fluorescing proteins from a collection of promoters that include myo-2, str-1, egl-17, mab-5, and various others, separately and in certain combinations. We present some proof of principle examples of how these could be used in genetic screens.

Miller D L et al. (2010) Aging, Metabolism, Stress, Pathogenesis, and Small RNAs, Madison, WI "Hydrogen Sulfide Protects Against Hypoxia Induced Protein Aggregation"

Miller D L, Roth M B

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

With age, the ability to maintain protein homeostasis declines. We have shown previously that low levels of hydrogen sulfide (H2S) increases lifespan and thermotolerance in the nematode C. elegans. Here we show that H2S also improves the ability to maintain protein homeostasis, as judged by the aggregation of polyglutamine (polyQ) containing proteins. Our data suggest that adaptation to H2S impinges on protein homeostasis through a mechanism that is distinct from the effects of H2S on lifespan. Remarkably, we have found that H2S also improves the ability to maintain protein homeostasis in stressful environmental conditions. We demonstrate that polyQ proteins aggregate in vivo when animals are exposed to specific hypoxic environments. The range of O2 concentrations that induce protein aggregation is modulated by genetic factors, including hif-1. Adaptation to H2S protects against hypoxia-induced protein aggregation, as animals pre-treated with H2S develop fewer protein aggregates when exposed to hypoxia. We have also observed that treatment with H2S after the hypoxic insult retards subsequent polyQ protein aggregation. These experiments show that polyQ-protein aggregation is induced both during and after exposure to hypoxia, which may have important clinical implications. Recently, it has been demonstrated that HIF-1 protein is stabilized and activated by H2S (Budde and Roth, 2010), suggesting the possibility that H2S acts through HIF-1 to modulate protein quality control mechanisms. Together, our studies show that H2S can have remarkably long-lasting physiological effects that can improve homeostatic mechanisms required to appropriately respond to subsequence environmental perturbations.

Julia Tischler et al. (2006) European Worm Meeting "Analysing the Redundancy of Duplicated Genes and the Evolutionary Conservation of Genetic Interactions Using Combinatorial RNAi in C. elegans"

Ben Lehner, Julia Tischler, Andrew G Fraser

[European Worm Meeting, 2006]

Julia Tischler, Ben Lehner and Andrew G Fraser Systematic analyses of loss-of-function phenotypes have been carried out for almost all genes in S. cerevisiae, C. elegans, and D. melanogaster, and there are major efforts to make a comprehensive collection of mouse knockouts. While such studies greatly expand our knowledge of single gene function, they do not address redundancy in genetic networks, nor do they attempt to identify genetic interactions. Developing tools for the systematic mapping of genetic interactions is thus a key step for exploring the relationship between genotype and phenotype. We thus sought to establish protocols for targeting multiple genes simultaneously by RNA interference (RNAi) in C. elegans to provide a platform for the systematic identification of genetic interactions in this key animal model system.. We set up conditions for RNAi that allow us to target multiple genes in the same animal (combinatorial RNAi) in a high throughput setting and to detect the great majority of previously known synthetic genetic interactions. We then used this assay to test the redundant functions of genes that have been duplicated in the genome of C. elegans since divergence from either S. cerevisiae or D. melanogaster, and identified 16 pairs of duplicated genes that are at least partially functionally redundant. Intriguingly, 14 of these redundant gene pairs were duplicated before the split of C. elegans and C. briggsae 80-110 million years ago. Our data provide the first systematic investigation into the redundancy of duplicated genes in any organism and strongly support population genetics models, which suggest that redundancy can be maintained over substantial periods of evolutionary time.. Furthermore, we set out to test whether systematically compiled yeast genetic interaction data can predict genetic interactions in the worm. We will present these data.

Brown, Andre et al. (2017) International Worm Meeting "A common format for worm tracking data."

Kerr, Rex, Brown, Andre, Lee, Chee Wai, Hokanson, Jim, Currie, Michael

[International Worm Meeting, 2017]

Many labs, including ours, have built a wide variety of worm trackers. These have a wide range of capabilities, from high-resolution imaging of single animals during calcium imaging, to very low-resolution imaging of animals as points. This diversity of capability enables the C. elegans community to address a wide range of problems at an appropriate scale. Most of these trackers also produce some data that is very similar to that of other trackers: animal position or spine, for example. Unfortunately, each tracker uses its own format to store data, so that any later analysis, despite being general in nature, cannot be performed on data from different machines. As the volume of tracking data grows, and the variety of downstream analysis methods expands, this limitation will pose an increasingly large barrier to replication of and extension of existing work across different labs. To address this issue, we have defined the Worm Common Object Notation, a set of rules for how to write tracking data in the ubiquitous JSON format, so that it can be easily shared between labs. To facilitate easy adoption of WCON, we have further written software in a variety of languages that will read or write data in WCON format. So far, we have implementations in Python, Scala, Matlab, and Julia, and wrapper libraries for Octave, R, and Java to use one of the main implementations. Additionally, the Tracker Commons project of which WCON is a part contains a small but rapidly growing set of pre-packaged analysis tools for routine manipulation of worm tracking data. We will also maintain a list of other WCON-compatible analysis tools as they become available. If you are involved in worm tracking, we invite you to adopt WCON and help make C. elegans behavioral data widely accessible. WCON is developed under the open source Tracker Commons project of the OpenWorm Foundation. We invite contributions and improvements!

Julia Grabitzki et al. (2006) European Worm Meeting "Identification of O-linked N-acetylglucosamine Modified Proteins in Caenorhabditis elegans"

Gunter Lochnit, Rudolf Geyer, Michael Ahrend, Brigitte Schmitz, Julia Grabitzki

[European Worm Meeting, 2006]

Julia Grabitzki1, Michael Ahrend2, Brigitte Schmitz2, Rudolf Geyer1 and Gnter Lochnit1. The posttranslational modification N-acetylglucosamine O-glycosidically linked (O-GlcNAc) to serine and threonine residues of proteins has been shown to be ubiquitous amongst eukaryotic proteins of the nucleus, cytoskeleton, cytoplasm, and has also been detected on cytosolic tails of membrane proteins [1]. O-GlcNAcylated proteins can form reversible multimeric complexes with other polypeptides or structures. The modification is often accompanied by phosphorylation/ dephosphorylation. O-GlcNAc can act either simultaneously or in a reciprocal fashion with phosphorylation. According to the Yin-Yang hypothesis, the phosphorylation/ dephosphorylation regulates O-GlcNAc-modified protein function (z.B. signal transduction and protein-protein interaction) in concert with phosphorylation [2-4]. The addition of O-GlcNAc to and the removal from the protein backbone is dynamic with rapid cycling in response to cellular signals or cellular stages.. Despite the fact, that Caenorhabiditis elegans is the best studied model organism, there have been no studies on O-GlcNAcylation in this organism so far. Therefore, to elucidate the role of O-GlcNAcylation, we investigated the proteome of a C. elegans mixed-stage population by two-dimensional gelelectrophoresis and subsequent western-blotting with the O-GlcNAc-specific antibody CTD 110.6 for the occurrence of this modification and identified the modified proteins by mass-spectrometry. We detected and identify several O-GlcNAc-modified proteins in C. elegans. Most of the identified proteins are involved in metabolic pathways. The prediction of the cellular localisation of the identified proteins revealed a predominant cytosolic occurrence of the O-GlcNAc modification.. References:. [1]. Rex-Mathes, M., J. Koch, Werner, S., Griffith, L. S and B. Schmitz. 2002. Methods Mol Biol 194: 73-87.. [2] Zachara, N.E. and G.W. Hart, Chem Rev, 2002. 102(2): p.431-8.. [3]. Griffith, L. S. and B. Schmitz. 1999. Eur J Biochem 262(3): 824-31.. [4] Wells, L. and G. W. Hart. 2003. FEBS Lett 546(1): 154-8.

Donavan TS Cheng et al. (2007) International Worm Meeting "A NON-ALIGNMENT GIBBS-SAMPLING BASED METHOD FOR SEQUENCE ELEMENT DETECTION USING PHYLOGENETIC CONSERVATION."

Donavan TS Cheng, Michael A Beer

[International Worm Meeting, 2007]

Current attempts to infer regulatory networks from genome-wide expression data require motif detection algorithms to identify transcription factor (TF) binding sites in the regulatory regions of co-expressed genes. These algorithms typically use either over-represention or phylogenetic conservation to predict TF binding sites. While these approaches have been successful in yeast [1,2,5], in larger genomes motif detection is significantly more challenging, and will likely require comparative genomics. Several recent algorithms have begun to combine these two sources of information to predict functional sites more accurately. [1,2] However, many rely on an initial global alignment of orthologous regulatory regions as a preprocessing step. Unfortunately, TFs generally recognize sites that are short and degenerate, and global alignment may be overly restrictive for the detection of such sites. We have developed a non-alignment based Gibbs sampling [3,4] algorithm that searches for over-represented sequence elements, conserved across orthologous regulatory regions in related species. Motif composition is represented probabilistically by a position weight matrix and a posterior probability score is used to assess the significance of the motif found. The algorithm employs a stochastic search to converge to optima and unlike other alignment-based techniques, does not require a prior estimate of the evolutionary relationship between species sampled. We compare the performance of our algorithm on synthetic data to that of existing algorithms that employ either over-representation, phylogenetic conservation, or both. We further validate our motif predictions on in vivo binding data in yeast. [5] We present novel motif predictions from sets of coexpressed genes C. elegans and the related sequenced nematode species C. briggsae, and C. remanei. 1. Siddharthan R, Siggia ED, van Nimwegen E. PLOS Comp. Biol. 1, e67 (2005). 2. Sinha S, Blanchette M, Tompa M. BMC Bioinf. 5, 170 (2004). 3. Roth FP, Hughes JD, Estep PW, Church, GM. Nat. Biotech. 16, 939-945 (1998). 4. Neuwald AF, Liu JS, Lawrence CE. Prot. Sci. 4, 1618-1632 (1995). 5. Harbison CT, Gordon DB, Lee TI, Rinaldi NJ, et al. Nature 431, 99-104 (2004).

Julia Grabitzki et al. (2006) European Worm Meeting "Phosphorylcholine-Modified Proteins of Caenorhabditis elegans are Specific to Developmental Stages"

Michael Ahrend, Gunter Lochnit, Julia Grabitzki, Rudolf Geyer

[European Worm Meeting, 2006]

Julia Grabitzki, Michael Ahrend, Rudolf Geyer and Gunter Lochnit. The free-living nematode Caenorhabditis elegans has been found to be an excellent model system for developmental studies [1] investigating parasitic nematodes [2] and drug screening [3]. Structural analyses of glycoconjugates derived from this organism revealed the presence of nematode specific glycosphingolipids of the arthro-series, carrying, in part, phosphorylcholine (PC) substituents [2]. PC, a small haptenic molecule, is found in a wide variety of prokaryotic organisms, i. e. bacteria, and in eukaryotic parasites such as nematodes. There is evidence that PC-substituted proteins glycolipids are assumed to be responsible for a variety of immunological effects including invasion mechanisms and long-term persistence of parasites within the host [4]. In contrast to PC-modified glycosphingolipids [5], only a limited number of PC-carrying (glyco)proteins were identified so far [6-9]. We have analysed the expression of PC-modified proteins of C. elegans during developmental stages using two dimensional SDS-Page separation, 2D-Western-blot and MALDI-TOF mass spectrometry. The pattern of PC-modified proteins was found to be stage specific. The PC-modification on proteins was most abundant in the egg and dauer larvae-stages followed by the adult-stage and L4. Only small amounts of the PC-substitution were found in L3 and L2. In L1 we couldnt detect any PC-Modification. The prediction of the cellular localisation of the identified proteins revealed a predominant cytosolic and mitochondrial occurrence of the PC- modification. Most of the identified proteins are involved in metabolism or in protein synthesis.. 1.. Brenner, S., Genetics, 1974. 77(1): p. 71-94.. 2.. Lochnit, G., R.D. Dennis, and R. Geyer, Biol Chem, 2000. 381(9-10): p. 839-47.. 3.. Lochnit, G., R. Bongaarts, and R. Geyer, Int J Parasitol, 2005. 35(8): p. 911-23.. 4.. Harnett, W. and M.M. Harnett, Mod. Asp. Immunobiol., 2000. 1(2): p. 40-42.. 5.. Friedl, C.H., G. Lochnit, R. Geyer, M. Karas, and U. Bahr, Anal Biochem, 2000. 284(2): p. 279-87.. 6.. Haslam, S.M., H.R. Morris, and A. Dell, Trends Parasitol, 2001. 17(5): p. 231-5.. 7.. Cipollo, J.F., C.E. Costello, and C.B. Hirschberg, J Biol Chem, 2002. 277(51): p. 49143-57.. 8.. Cipollo, J.F., A.M. Awad, C.E. Costello, and C.B. Hirschberg, J Biol Chem, 2005. 280(28): p. 26063-72.