“Having only 302 neurons, C. elegans is a good learner.”
Learning is the act of acquiring new or modifying and reinforcing existing knowledge, behaviors, skills, values, or preferences which may lead to a potential change in synthesizing information, depth of the knowledge, attitude or behavior relative to the type and range of experience.
The learning behavior of C. elegans (Caenorhabditis elegans) has been studied for a long time. Worms are demonstrated to possess both non-associative and associative learnings induced by intermittent stimulation of chemicals or heavy metals .
However, the main drawback of these studies is chemical stimuli cannot be withdrew cleanly. The the residual chemicals will make it impossible to avoid the stimuli cross-contamination. They will make the results difficult to interpret. We use synthetic biology method to establish to overcome this obstacle. The key components that help us solve this issue are hardware and model:
Expression of two types of channelrhodopsins in two pairs of receptor neurons enable us to use blue and red lights to train worms, for example, to be addicted to alcohol.
Two microfluidic chips are designed to study worms’ behavior change at the group level and measure the activation signal of individual neuron after stimulation.
So far, our project has been almost completed. With the expression of Chrimson and CoChR on AWA and AWB neurons , C. elegans shows preference to the blue light and repulsion to red light. After induced by the blue light for 2 hours, the engineered worms are strongly attracted by alcohol, while the wild worms have no preference to it.
Thus, our project demonstrates the establishment of light-inducing learning process in C. elegans.See details
Our further work is to decipher the change of neuron connectivity due to the newly learned behavior. Using the optofluidics platform above, we are able to analyze the activation of downstream neurons in the new-formed or modulated neural circuit. See details
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