Epigenetic modification is a change to gene expression or cellular phenotype that is caused by alterations that don't involve the underlying DNA sequence. Because all cells in your body contain the exact same genes, these epigenetic changes help determine which genes different cells express, allowing them to develop specialized functions.
The pancreas consists of insulin-secreting beta cells and glucagon-secreting alpha cells. Insulin serves as a signal for cells in the body to take up glucose, while glucagon opposes this effect; malfunction of these cells leads to the development of diabetes. In Journal of Clinical Investigation, Klaus Kaestner and colleagues at the University of Pennsylvania identified epigenetic modifications that distinguish pancreatic beta cells from alpha cells.
Additionally, Kaestner and colleagues found that they could reprogram alpha cells to function as beta cells by mimicking the epigenetic modifications found in beta cells through treatment with a drug known as a histone methyltransferase inhibitor. These studies suggest that epigenetic manipulation could be used to generate replacement cells for diseases such as diabetes, in which patients lack functional beta cells.
In a companion commentary, Larry Moss of Duke University discusses how these cells might serve as an important resource in both research and therapeutic development.
TITLE:Epigenomic plasticity enables human pancreatic α- to β-cell reprogramming
ACCOMPANYING COMMENTARY - Creating new beta cells: Cellular transmutation by genomic alchemy