McLarnon, Caitlyn et al. (2011) International Worm Meeting "Oxidative stress induces loss of GFP labeled neurons and delayed development to adulthood in an unc-13 mutant."

Kohn, Rebecca E., Minniti, Alicia N., Frymoyer, Christopher, Inestrosa, Nibaldo C., McGee, Caitlin, Roth, Elizabeth, King, Lauren, Gurenlian, Laura, McLarnon, Caitlyn

[International Worm Meeting, 2011]

We are interested in understanding how changes in neurotransmitter release affect sensitivity of Caenorhabditis elegans to oxidative stress. Oxidative stress can occur when cells fail to neutralize reactive oxidative species. Nucleic acids, lipids, and proteins can be damaged in response to oxidative stress and affected neurons may undergo neurodegeneration. Activity in neurons can confer resistance to oxidative stress. Products of the unc-13 gene regulate neurotransmitter release from all neurons in C. elegans and defects in this gene result in decreased abundance of neurotransmitters in synapses and paralysis. When wild type C. elegans are exposed to oxidative stress, there is a delay in the development of worms to adulthood. Following exposure of unc-13 mutants to the chemical paraquat, which induces oxidative stress, we found that unc-13 worms develop to adulthood later than wild type. Using strains with GFP labeled neurons, we examined the number of GABAergic, dopaminergic, and serotonergic neurons in worms with a normal functioning nervous system and with a mutation in unc-13 following exposure to paraquat. There was a decrease in the number of GFP labeled neurons and more neurons were missing in the unc-13 strain. These findings suggest that unc-13 mutants with decreased neurotransmitter release have increased sensitivity to oxidative stress. We plan to perform experiments to determine whether the GFP labeled neurons are undergoing apoptosis or necrosis.

Bell, Taylor et al. (2011) International Worm Meeting "A writing intensive Caenorhabditis elegans laboratory exercise for undergraduates examining oxidative stress and antioxidants."

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.