Ingrid Wickelgren
Over the past decade or so, molecular biologists have learned that cells use various combinations of the proteins called transcription factors to turn genes on and off. But recent research has shown that the precise three-dimensional shapes of those transcription factor complexes are just as critical for correct gene control as the identities of the proteins that make them up. What's more, these shapes are often sculpted with the aid of "architectural proteins," which are themselves part of the complexes and which help assemble them by forcing large bends into the DNA to which the complexes bind.