Advisor: Hang Lu, Ph.D. (Georgia Institute of Technology)
Patrick McGrath, Ph.D. (Georgia Institute of Technology)
Mark Styczynski, Ph.D. (Georgia Institute of Technology)
Robert Butera, Ph.D. (Georgia Institute of Technology)
Yun Zhang, Ph.D. (Harvard University)
MICROFLUIDIC-BASED TOOLS AND METHODS FOR COMPLEX CHEMOSENSORY AND CHEMOTAXIS STUDIES IN C. ELEGANS
There is a great interest in studying behavior and the underlying biological basis for behaviors in small model organisms. Some properties of C. elegans that greatly facilitate genetic investigations are its small size, relatively simplistic ‘brain’, complex repertoire of behaviors, and ease of isogenic population studies. In order to take full advantage of these characteristics, it is desirable to have methods for analyzing behaviors of large populations of animals in well controlled environments. One set of behaviors extensively used to investigate numerous phenomena in neurobiology within C. elegans deals with the navigation of chemical environments (chemotaxis). Studies based on C. elegans chemotaxis are used in investigating chemosensation, innate preferences, learning, memory, and more. We have improved upon previous microfluidic and computer-vision technologies to advance C. elegans chemosensation and chemotaxis studies to answer more sophisticated biological questions. One developed method is a microfluidic device capable of monitoring animal neuronal activity in vivo while delivering multiple chemical stimuli to animals at sub-second speeds and in any desired order. This method facilitates investigations as to how complex environmental stimulus changes are encoded within a simple, well-characterized nervous system at relevant behavioral timescales. The second developed method is a microfluidic platform and accompanying software capable of tracking a population of C. elegans freely navigating well-controlled, spatial chemical environments over long timescales. Via this method, complete behavioral and stimulus experience history profiles can be generated for each animal within a population. This enables correlations to be made between acute chemotaxis behaviors and animal stimulus histories which provides unique opportunities for novel insights into C. elegans neurobiology studies.