Science and Mathematics Faculty Presentations

Document Type

Poster Session

Event Date



American Society for Cell Biology Conference


San Francisco, CA


The netrins are a family of signaling proteins expressed throughout the animal kingdom. Netrins play important roles in developmental processes such as axonal guidance and angiogenesis. Netrin-1, for example, can act as either a chemoattractant or a chemorepellent for axonal growth cones depending upon the concentration of the protein as well as the cell type. Netrin-1 acts as a growth factor in some cell types and is expressed by some tumor cells. Netrin-3 appears to share some signaling apparatus with netrin-1, but is less widely expressed, and its physiological roles are much less understood.

Tetrahymena thermophila are free-living, eukaryotic, ciliated protozoa used as a model system for studying chemorepellents and chemoattractants because their swimming behavior is readily observable under a microscope. We have previously found that netrin-1 peptide acts as a chemorepellent in Tetrahymena thermophila at concentrations ranging from micromolar to nanomolar. However, netrin-1 peptide does not affect growth in Tetrahymena at these concentrations. In our current study, we have found that related peptides, netrin-3 peptide (H-19 and C-19; Santa Cruz Biotechnology), act as chemorepellents in Tetrahymena thermophila at concentrations at or below 1 μg/ml. The same concentration of netrin-3 peptide reduces growth of Tetrahymena cultures by approximately 75%. We are currently conducting further studies to determine the mechanism through which these peptides are signaling.


Netrin-3 peptide, chemorepellents, growth inhibitors, Tetrahymena thermophila

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.



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