Olaf Bossinger et al. (2005) International Worm Meeting "Development of the C. elegans intestine"

Robin Schneider, Olaf Bossinger, Heleen Arts, Tobias Wiesenfahrt

[International Worm Meeting, 2005]

The C. elegans intestine is a simple epithelial tube that consists of only 20 cells (E-cells). We wish to understand how this organ assembles during embryonic development. Here, we are concentrating on three different aspects of intestinal organogenesis. First, we are using temperature sensitive mutants and RNAi to investigate the role of the microtubule cytoskeleton during epithelial polarization. Second, we reinvestigate the role of endocytosis (Rouxs Arch. Dev. Biol. 205, 494-497) with regard to the remodelling of the apical junctional pattern. Finally, we wonder how intestinal cells become correctly assembled into an epithelial tube. In apr-1(RNAi) embryos the gut epithelium shows an aberrant junctional pattern without any obvious defects in apicobasal polarity and the epithelial tube is still formed. With the help of immunofluorescence analysis and 4D-microscopy, we are concentrating on the question whether the increased number of intestinal cells is the result of cell fate transformation or hyperplasia within the E-lineage. Prelliminary data will be presented and discussed.

Peters, Maureen A. et al. (2011) International Worm Meeting "Combining old fashioned gene mapping and new fangled genetic analysis in an upperlevel Genetics course."

Peters, Maureen A., Cullen, Katherine

[International Worm Meeting, 2011]

Integrating a Genetics laboratory into a complementary lecture course strengthens the understanding of genetic concepts and introduces the process of experimental investigation. Five iterations of a combined lecture and lab course have been offered at a small liberal arts college, with each enrolling twenty or fewer students. Weekly three-hour lab meetings are scheduled. Students must also work outside of class time to complete the long-term experiments. The lecture portion of the class covers classical and molecular genetics with a focus on problem solving and genetic analysis. The lab portion is divided into two experimental sequences: the first uses classical genetics, the second, molecular biology and/or reverse genetics. The classical sequence focuses on the concepts of dominance, chromosomal segregation, linkage, and recombination. Each pair of students are given a C. elegans uncoordinated (Unc) mutant whose identity is unknown. Students perform a dominance test, map their mutant to an approximate genetic map position, identify a candidate Unc using Wormbase and test their predication using a complementation test. This series of experiments builds microscopic manipulation and experimental planning skills, data analysis expertise, and provides familiarity with C. elegans biology and bioinformatic resources. The molecular biology and/or reverse genetics sequence advances student understanding of one of the concepts covered in the classical sequence, but does so through the active research program of a department member. In this latter portion, the lab emulates an active research lab, with each student engaging in open ended experiments. Thus this portion of lab varies each year. Several experiments have utilized single nucleotide polymorphism (SNP) mapping of single or double mutants. RNA interference screens using a feeding bacterial library have also been performed. Students generally enjoy the independence and engagement provided by these investigative lab experiments as well as the integration of lecture concepts in lab exercises. Pre- and post-test surveys suggest that students gain confidence in their ability to analyze data and to propose new experiments.

Hill, Robin L. (2011) International Worm Meeting "Characterizing wild nematode isolates in an undergraduate research lab."

Hill, Robin L.

[International Worm Meeting, 2011]

Small Public Liberal Arts Colleges pose multiple challenges, particularly in teaching laboratory courses. Resources are limited and the majority of students have no lab experience. In addition, faculty struggle to maintain a full-time active research program due to heavy teaching loads. A significant percentage of students expressing an interest in the sciences also express a desire for graduate or professional studies. As many of these programs desire "hands-on" scientific experience, providing research opportunities could be vital to their future success. To address these issues, a full semester research-based project was developed around isolating and identifying wild nematode isolates. An overview of nematode phylogeny and population genetics studies is coupled with students working in small groups to develop a research project, isolate nematodes and characterize the isolates using morphological and molecular analysis. Results are presented in a format similar to graduate lab meetings. The molecular techniques utilized during the pilot project included species-specific PCR (glp-1) (1) as well as sequencing of the 18S ribosomal RNA gene (2). I adapted universal rice primers (URP) as a fingerprint assay (3). Morphological analysis included buccal (lips, buccal tube, pharynx) and tail (shape, papillae and spicule structure) morphology as well as mating system (gonochoristic vs. hermaphroditic). Strains from the CGC have been used for comparison (both morphological and molecular) to wild isolates. Mating crosses with C.elegans and C.briggsae males have been performed with hermaphroditic species. Males from gonochoristic strains can be employed for gonochoristic isolates. Hermaphroditic isolates were obtained from leaf litter in wooded settings, open grasslands and under a rotting pumpkin. Species-specific PCR as well as mating crosses reject identification as C.elegans or C.briggsae. Sequencing of the 18S RNA gene is ongoing. Gonorchorisitc isolates were obtained from both household and grass cutting compost. Morphological analysis based on tail morphology suggests the genus Rhabditis, subgenus Rhabditella and Cephalopoides. Student feedback was uniformly positive. Isolates were easily obtained and the self-directed nature of the projects deepened their understanding of lab methods and research design. The range of analysis methods allows the course to be adapted to resource availability, therefore providing a method of research experience while enhancing knowledge of the model species. (1) Barriere, A., and Felix M.A. (2005). Curr. Biol. 15,1176-184. (2) Floyd, R. et al. (2002). Mol Ecol. 11, 839-850. (3) Kang, H. W. et al. (2002). Mol. Cells. 2, 281-287.

Clark, Meaghan et al. (2015) International Worm Meeting "C. elegans as a tool to study gonad development in a small liberal arts context."

Zarazua, Brenda, Denman, Audrey, Heilig, Mara, Dokko, Soobin, Snell, Groover, Crook, Matt, Scott, Lindsey, Wieneke, Arika, Clark, Meaghan, Palacios, Jessica

[International Worm Meeting, 2015]

The research experience and introduction to the scientific method are vital components of an undergraduate's science education. Similarly maintaining an active research program as a professor at a small liberal arts college is critical to success on the tenure track. However, limited resources and time make achieving these two ideals a challenge. We sought to address this dilemma by undertaking a novel hypothesis driven research project within the somewhat flexible limits of the lab section of our BIOL329 Developmental Biology course, using C. elegans as a model to study reproductive development. Our task was to characterize five kinases that had been briefly characterized as being required for uv1 cell specification; bub-1, cdk-1, cdk-12, plk-1 and wee-1.3. Using RNAi and phase capable inverted microscopes we spent the semester quantifying the effects of RNAi knockdown of these genes on gonad development. cdk-1 RNAi resulted in a highly penetrant lack of both gonad arms in 100% of animals with a small genital primordium persisting into late L4 stage, suggesting a role for cdk-1 in early gonad specification. bub-1 and plk-1 RNAi resulted in occasional absences of both or single gonad arms, with the anterior gonad arm most frequently absent or misshaped. wee-1.3 RNAi caused a curious "wiggly gonad" phenotype where gonad length and location of the DTC were similar to wild-type animals, but the distal gonad arm took a meandering course to its destination, which may suggest a possible gonad guidance role for wee-1.3. Finally, cdk-12 RNAi resulted in a wide range of phenotypes such as a lack of gonad arms, Vul, Bagging, exploding vulva and others, implicating cdk-12 in a wide range of related developmental processes. Interestingly, all these genes have been studied to varying extents in the context of cell cycle control yet their roles in gonad development are far less well known. Thus, in the space of a semester we have characterized genes involved in several different stages of gonad development and have begun the process of elucidating their precise roles and partners. This process has been of immeasurable value to the students and has demonstrated that carrying out research in the context of a course lab section is both possible and productive.

Katz, David et al. (2021) International Worm Meeting "The Pipeline CURE: lowering institutional barriers to research by reiteratively incorporating original C. elegans experiments throughout a biology curriculum"

Lee, Teresa, Schmeichel, Karen, Katz, David, Carpenter, Brandon

[International Worm Meeting, 2021]

Participation in research provides personal and professional benefits for undergraduates. However, some students face institutional barriers that prevent their entry into research, particularly those from underrepresented groups who may stand to gain the most from research experiences. Course-based undergraduate research experiences (CUREs) effectively scale research availability, but many only last for a single semester, which is rarely enough time for a novice to develop proficiency. To address these challenges, we established a Pipeline CURE. The Pipeline CURE integrates C. elegans epigenetics research being conducted by the Katz Lab at Emory University throughout the biology curriculum at Oglethorpe University, a nearby liberal arts college. Students are introduced to C. elegans with their first course in the major. After revisiting the research system in several subsequent courses, students can choose to participate in an upper-level research experience, led by an NIH Institutional Research and Academic Career Development Award (IRACDA) postdoctoral fellow from the Katz Lab. Preliminary data taken during implementation of The Pipeline CURE suggests that the reiterative CURE strategy can recapitulate benefits of a traditional apprenticeship lab experience entirely within the curriculum in a classroom setting. These benefits associated with The Pipeline Cure include including replacing beginner confidence with mastery and resilience via repeated exposure to the same research system. As a result, the Pipeline CURE levels the playing field by giving underrepresented students the chance to experience original research, and potentially conduct honors thesis research, without having to seek out a traditional apprenticeship lab experience. The research experience gained by students can serve as an entry to STEM careers, or provide a platform for competing for admission to graduate programs. In addition, the data generated can open new areas of research and help facilitate publication of manuscripts. As an added benefit, The Pipeline CURE also exposes postdoctoral fellows to challenges that underrepresented groups face in the classroom. Thus, by uniting evidence-based teaching methods with ongoing scientific research, the Pipeline CURE provides a new model for overcoming barriers to participation in undergraduate research, that is flexible enough to be implemented at a range of institutions using a variety of research questions.