In the developing brain, nerve cells make connections with one another by extending processes, often over long distances. The growing tips of these nerve cell processes are guided to their ultimate connection sites by molecular cues in the environment.
A Salk Institute research team has discovered a receptor-protein interaction that guides nerve cells along specific pathways. John Thomas, professor of molecular neurobiology, working on the fruit fly Drosophila, found that a protein called Wnt5, a member of a large family of signaling molecules, binds to a receptor called Derailed present on the surface of growing nerve cells.
This binding guides the tips of these nerve cells to their final destination by preventing them from entering the wrong pathway. This mechanism appears especially important for nerve cells that extend processes across the midline to make connections on the opposite side of the nervous system, a prominent class of nerve cells also found in vertebrates.
This research could have implications for understanding birth defects as well as the regeneration of nerve cells.