An Examination of Chemotaxis in Planarians
Planarian regeneration has remained very mysterious to researchers for hundreds of years. Although these flatworms (phylum Platyhelminthes) are relatively simple, they continue to be enigmatic. The regenerative process begins when a portion of a planarian is amputated; epidermal cells change their shapes and cover the wound with epithelium. Next, undifferentiated cells called neoblasts proliferate under this epidermal cell layer and form the regeneration blastema that will eventually replace the missing body structures. A fragment can regenerate into a complete planarian in the period of about two weeks. In order to learn more about this process, the genes involved in regeneration have to be identified. One way to study gene function is to inhibit gene _expression by introducing double-stranded RNA (dsRNA) into the planarians. One method for introducing dsRNA is to induce consumption of dsRNA-expressing bacteria in the planarians. To optimize these feeding protocols one has to know which components of planarian food induce a feeding response. Therefore, chemotaxis experiments have been performed to identify factors required for feeding. The chemicals contained in planarian food that were tested include: glutathione, glutamine, lysine, and various fatty acids (to be tested). Glutathione provoked no response when tested as a chemo-attractant. Lysine and glutamine attracted the planarians to the food; however, neither of them induced planarian feeding.
School:
University of Illinois at Urbana-Champaign
Department:
Premed. Biology
Research Advisor:
Phillip Newmark
Department of Research Advisor:
Cell and Structural Biology
Year of Publication:
2002