Ling, Linsay, Mendoza, Steve, Sherry, Tim, Nowak, Nathaniel, Arisaka, Katsushi, Jiang, Karen, Haller, Leonard
[
International Worm Meeting,
2015]
Perception and navigation through space require accurate translation and transmission of sensory input to motor output. On a linear temperature gradient, Caenorhabditis elegans demonstrate a distinct behavioral phenotype in which they frequently travel along isotherms, maintaining sensitivity within 0.05 degC. This isothermal attractor state is correlated with movement at a constant and maximal velocity. We investigate how AIY, a first layer interneuron and postsynaptic partner to AFD thermosensory neuron, is able to integrate thermal information to return specific well-defined behavioral phenotypes. Prior observations of neural activity in vivo involve partial paralysis or constraint of the worm while stimuli is applied. Other systems circumvent this limitation by re-centering the stage; this generates an external force during stage acceleration introducing another stimulus. We overcome these two primary obstacles through the implementation of a novel automated worm-tracking epi-fluorescent microscope. The three-camera microscope system mounted on a movable XY stage captures dynamic Ca+2 signals in Cameleon-labeled neurons while the nematode navigates unconstrained along the temperature gradient. Implementing this set up, we observed that the greatest temperature difference occurs between the extremes of the head movement while along isotherms which phase lock with fluorescence response in AIY. The steady Ca+2 waveform in AIY suppresses reversals and maintains high speeds to downstream motor circuitry. .
Atamdede, Sean, Haller, Leonard, Kao, Michelle, Mendoza, Steve, Madruga, Blake, Agarwal, Neha, Nowak, Nathaniel, Sunyoto, Amanda, Sherry, Tim, Jiang, Karen, Cheng, Shirley, Vanmali, Bobby, Trusz, Guillaume, Arisaka, Katsushi, Pellionisz, Peter, Woolfork, De'Marcu, Sagadevan, Addelyn, Kim, Taejoon, Ling, Linsay, Lam, Brian
[
International Worm Meeting,
2015]
For students, the study of model organisms presents an opportunity to learn various general science and research disciplines; however, each model organism has it's own set of advantages. Chiefly, Caenorhabditis elegans are excellent model organisms to study neuroscience and biophysics due to its availability, tractability, relatively simple nervous system, and it's patently observable behavior. Here in the Elegant Mind Club at UCLA, we provide undergraduate students a unique hands-on experience working with C. elegans and a chance to present their own scientific methods of interest, allowing them to explore the nature of scientific research and understand the conclusions drawn from their data. In our laboratory, undergraduate students are entirely responsible for maintaining and culturing the worms as well as building and refining their experimental systems. Direct involvement with the biological samples teaches students the discipline of working with chemicals and maintaining sterility. Published papers and online resources such as WormBook, WormAtlas, and Caenorhabditis Genetics Center provide students with a source of well-established methods and techniques to serve as a basis for their own studies. Manual practice in hardware development permits students to personally hone their experiment to be the most controlled and reproducible systems. As of now, systems for thermotaxis, electrotaxis, chemotaxis, phototaxis, durotaxis, as well as behavior within a magnetic field and the absence of stimuli have been reproduced and improved by our members. Our laboratory begun with a few core members and have expanded to accommodate more than 80 students from different universities over the world and we hope to encourage more students to approach scientific research with enthusiasm.