How semaphorins keep your taste system in order As we reported yesterday, scientists have recently discovered how the human taste system stays intact when individual taste cells die off every two weeks. Today’s Video of the Day comes from Columbia University and features a closer look at semaphorins, the special molecules that help guide neurons to the correct taste cells.
Semaphorins have been discovered in the early 1990s as repulsive axon guidance molecules, enabling axons to find their targets and thus contributing to nervous system development. Semaphorins are found in the nervous system not only during development but also in adulthood.
We already knew two parts of the taste equation: taste-receptor cells on the tongue—which actually interact with your food—and the neurons that tell the brain what it’s tasting. Each taste-receptor cell can only respond to one taste (sweet, bitter, sour, salty or umami—a savory taste), and neurons are just as specific.
Your ability to taste comes from tiny molecules released when you chew, drink, or digest food; these molecules stimulate special sensory cells in the mouth and throat. These taste cells, or gustatory cells, are clustered within the taste buds of the tongue and roof of the mouth, and along the lining of the throat. Also as shown above in video How semaphorins keep your taste system in order will show you how the whole system works.
Video Credit: Columbia University