The gene, SOX2, stimulates stem cells on the surface of the embryonic tongue and in the back of the mouth to transform into taste buds, according to the researchers. Stem cells are immature cells that can develop into several different cell types depending on what biochemical instructions they receive.
"Not only did we find that SOX2 is crucial for the development of taste buds, but we showed that the amount of SOX2 is just as important," said Brigid Hogan, Ph.D., chair of the Duke University Medical Center Department of Cell Biology and senior member of the research team. "If there isn't enough SOX2 present, or if there is too much, the stem cells will not turn into taste buds."
The researchers made their discovery in mice, but they believe the same process occurs in humans.
According to the researchers, the findings will help scientists better understand how the behavior of certain stem cells is controlled. The SOX2 gene is already known to be crucial in controlling whether embryonic stem cells remain undifferentiated and whether stem cells in the brain, eye and inner ear differentiate into specialized nerve cells.
Taste bud cells, much like skin cells, continually slough off and are replaced by new ones. So the new findings not only provide insights into the interactions between SOX2 and tongue stem cells during embryonic development, but also into how stem cells continue to operate in adults, the researchers said.
The researchers published the findings in the October 2006 issue of the journal Genes and Development. The work was supported by the National Institutes of Health.
Their findings were entirely serendipitous, Hogan said.
"In my laboratory, we were studying the role of SOX2 in the development of the lung, esophagus and the gut in embryonic mice" she said. "We were quite surprised when we accidentally found
Source:Duke University Medical Center