Ryan, Rabiul, King, Lauren, Slaunwhite, Erin, Murley, Kathleen, March, Amanda, Bell, Taylor, Kohn, Rebecca E., Murphy, Katherine, Betzu, Justine, Pall, Matthew, Hartl, Amy, Frymoyer, Christopher, Brown, Loreal, Fontana, Marissa, Hamilton, Christina, McLarnon, Caitlyn, Meeley, Lauren
[
International Worm Meeting,
2011]
An open-ended laboratory exercise was developed for an undergraduate Molecular Neurobiology course. The goal of the exercise was for students to design and carry out an experiment to examine how oxidative stress affects Caenorhabditis elegans strains with mutations affecting nervous system function and whether an antioxidant could protect the worms from damage. A writing intensive component of the laboratory was included for students to submit their findings to a peer-reviewed journal. This exercise would be accessible for a variety of upper level courses, including neuroscience and cell biology. Students successfully designed their experiments based on information in the Materials and Methods sections in related scientific journal articles. Students chose conditions for inducing oxidative stress and for incorporating an antioxidant in the experiment. The professor teaching the course and a student teaching assistant experienced with C. elegans research guided students in experimental design, trouble shooting difficulties, and analyzing findings. Students' results showed that strains with defects in neurotransmitter release had a higher percentage of lethality than a strain with a wild type nervous system. The antioxidant they chose to work with, L-ascorbic acid, decreased the percentage of lethality for some strains. Students worked in groups of four during scheduled laboratory times as well as during additional times to maintain their strains and perform experimental trials. During laboratory meeting times, students spent part of their time discussing effective approaches for writing scientific papers. Drafts of student manuscripts went through student peer-review and review by their instructor to prepare for submission to a journal. Three student groups chose to submit their manuscripts to the journal, IMPULSE, An Undergraduate Journal for Neuroscience, and one group chose to submit to The Journal of Young Investigators. Both journals are designed for undergraduate authors.
[
International Worm Meeting,
2019]
C. elegans lifespan is shortened by mating, but must be delayed long enough for successful reproduction. Susceptibility to brief mating-induced death increases with age; surprisingly, this is not due to declining health, but to loss of protection upon self-sperm depletion. Self-sperm maintains expression of a DAF-2 insulin-like antagonist, INS-37, which promotes the nuclear localization of HLH-30/TFEB, a pro-longevity regulator. Mating induces the agonist INS-8, promoting HLH-30 nuclear exit and subsequent death. In opposition to the protective role of HLH-30 and DAF-16/FOXO, TOR/LET-363 and the IIS-regulated Zn-finger transcription factor PQM-1 promote seminal-fluid-induced killing. Self-sperm maintenance of nuclear HLH-30/TFEB allows hermaphrodites to resist mating-induced death, increasing the chances that mothers will survive through reproduction. The hijacking of the IIS pathway by males is combated by the mother's expression of an insulin antagonist that keeps her healthy through the activity of pro-longevity factors, as long as she has her own sperm to utilize. ** If possible, I would prefer that this abstract please be considered with the abstract submitted by Lauren N. Booth, Travis J. Maures, Robin W. Yeo, and Anne Brunet ("Self-sperm induce resistance to the detrimental effects of sexual encounters with males in hermaphroditic nematodes").