Biologists at Washington University in St. Louis have made major headway in explaining a mechanism by which plant cells silence potentially harmful genes.
Differential gene expression profoundly influences the way in which organisms grow and develop. For instance, although every cell in the human body has the same genetic information, different subsets of the DNA get activated to make an eye different from a toe. RNA polymerases, the enzymes responsible for making RNA from DNA templates, are key players in determining which genes get switched on and which get left off.