Taste may be the least understood of our five senses. Even basic questions, like where do taste buds come from, remained mysterious. Until now. In a study published in the journal Stem Cell, scientists have identified the elusive "parental" cell that give rise to the daughter cells responsible for taste. [Karen K. Yee et al., Lgr5-EGFP Marks Taste Bud Stem/Progenitor Cells in Posterior Tongue]

Taste buds are made of clusters of taste cells, which contain the receptors for sweet, salty, sour, bitter and umami. They’re concentrated in the bumpy papillae that cover the tongue’s surface. But taste buds are not static structures. Their resident taste cells live only about two weeks before being replaced by newborn baby taste cells. After all, a pizza burn is not permanent. But no one knew the address of the taste cell nursery.

To track it down, scientists scanned the tongue for cells that produce the same marker protein as the body’s other stem cells, which give rise to our other specialized cells. The researchers discovered a reservoir of stem cells that line the trenches around the papillae at the back of the tongue.

These stem cells can produce all of the different taste cell types, and so allow us to savor all of life’s flavors.

—Karen Hopkin

[The above text is a transcript of this podcast.]