What determines how a cell’s genome is regulated to ensure proper growth and development? Turns out, the parts of the genome that are turned on or off in each cell-type or tissue play a major role in this process. Now, a research team has shown that the CLASSY gene family regulates which parts of the genome are turned off in a tissue-specific manner. The CLASSYs essentially control where the genome is marked by DNA methylation—the addition of methyl chemical groups to the DNA that act like tags saying, “turn off.” Because DNA methylation exists across diverse organisms, including plants and animals, this research has broad implications for both agriculture and medicine.
