Investigators at St. Jude Children’s Research Hospital have discovered how a single molecular “on switch” triggers gene activity that might cause effects ranging from learning and memory capabilities to glucose production in the liver.The “on switch,” a protein called CREB, is a transcription factor—a molecule that binds to a section of DNA near a gene and triggers that gene to make the specific protein for which it codes. CREB activates genes in response to a molecule called cAMP, which acts as a messenger for a variety of stimuli including hormones and nerve-signaling molecules called neurotransmitters.
