Stem cells’ light signatures improve understanding of aging in the brain
A UW–Madison team led by Darcie Moore, professor of neuroscience, discovered how to use the light naturally thrown off by biological specimens — autofluorescence — to better study the different states of stem cells in the nervous system. Autofluorescence is particularly useful in studying stem cells’ dormant state, known as quiescence. “The quiescent state is very important,” says Moore. “It is the rate-limiting step in making newborn neurons in the adult brain. Aging and neurological diseases limit this exit from quiescence.” Moore collaborated with Melissa Skala, a UW–Madison biomedical engineering professor, to explore a new way of identifying whether an adult neural stem cell was quiescent or active. When cells shift from active to quiescent states, the presence and abundance of certain proteins alters the way light is absorbed and emitted back out of the cell. By focusing on light emitted by parts of the cell that change with quiescence, the researchers identified the light “signature” that matches a target cell state. Identifying and decoding these autofluorescence signatures offers researchers a new tool that can aid in studying adult neurological diseases and aging, and potentially expand beyond neuroscience.