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Cell Identity

How do stem cells stay stem cells?

Mesenchymal stem cell Mesenchymal stem cell (Photo/Robert M. Hunt)

Human embryonic stem cells—those that grow to form all the cells in the adult body—are only one type of stem cell. All adult tissues contain their own stem cells that step in to repair or replace tissue damaged from disease or injury. How do these cells stay in their undifferentiated state until called to duty?

Cell biologist Erika Matunis studies how cells slated to become sperm in the fly testis can de-differentiate and revert back to their original stem cell fate.

A pioneer in the field of epigenetics, Andrew Feinberg, studies how embryonic stem cells differ from adult stem cells, and how stem cells change as they go from a stem cell to an adult blood cell. Epigenetic changes occur outside of the DNA sequence and appear as alterations in chemical groups attached to the DNA, which can control what genes are turned on or off.