Scientists Discover How to Unlock Inaccessible Genes

Biologists from China, France, Spain, and the United States have discovered how specialized enzymes remodel the extremely condensed genetic material in the nucleus of cells in order to control which genes can be used.

According to B. Franklin Pugh of Penn State University, one of the corresponding authors, they knew that the compaction into chromatin makes genes inaccessible to the cellular machinery for gene expression, and that enzymes opened up the chromatin to specify which genes were accessible and could be expressed in a cell, but they did not know the mechanism by which the enzymes functioned.

The research team first mapped the location of several "chromatin-remodeller enzymes" across the entire genome of the embryonic stem cells of the mouse. It showed that remodeller enzymes bind to particular nucleosome "beads" at the sites along the wrapped-up DNA that are located just before the gene sequence begins. They then tested how the chromatin-remodeller enzymes impact gene expression by reducing the amount of each of these enzymes in embryonic stem cells. The scientists found that some chromatin-remodeller enzymes promote gene expression, some repress gene expression, and some can do both.

For more details, read the news article at Penn State News.