Our research program uses molecular genetic and physiological techniques to understanding a multi-cellular signaling system in a small nematode named Caenorhabditis elegan (C. elegans ). C. elegans is also affectionately called “worm” by its greatest fans. This transparent, soil-dwelling nematode was carefully chosen to serve as a model system for studies of eukaryotic organisms in the early 1970s. Similarities between the genetic make-up of this organism and human beings have resulted in important discoveries related to human health. My research program specifically targets the digestive motor program, a behavior that occurs roughly every fifty seconds. The program is comprised of three stereotyped, sequential muscle contractions: a contraction of the posterior body wall muscles, followed by contraction of the anterior body wall muscles, and finally by contraction of the enteric muscles.
To understand this one-minute digestive rhythm at the cell and molecular level, the components of the system must be identified and then studied in detail. This work involves identifying and characterizing genetic mutants with defects in the digestive rhythm. Each gene is studied in a sequential series of research steps: (STEP 1) identification of a gene involved in the process by analysis of a mutant, including subsequent rescue (e.g. introduction of the normal version of the gene into mutant animal results in a normal animal); (STEP 2) analysis of the site of the gene’s action (where in the worm’s body does it function, i.e. in the intestine, or the neurons; in the nucleus or the mitochondria); (STEP 3) generation and testing of models of its mechanism of action (i.e., does it keep track of the motor program's timing or does it signal a muscle to contract). The completion of these steps gives a mechanistic understanding of what the product of the gene (i.e. the protein) does in the system at the level of molecular changes in the cell or tissue. The genes, or more specifically the products encoded by the genes, can act in any facet of the motor program such as the timing of the cycle, or to cause one of the muscle contractions.
