Although the DNA and its double-helix are one of the most familiar molecules of our time, our knowledge of how cells control what genes they want to express is still rather limited. In order to create, for example, an enzyme, the information that's inscribed in our DNA about this enzyme needs to be transcribed and translated. To start this highly complex process, special regulatory proteins called transcription factors (TFs) bind to specific DNA regions. That way, they can turn the expression of a gene on and off. The big question is: How can transcription factors find the right place on the DNA to properly regulate gene expression?