One of the great challenges in nanotechnology is the programmed control of hierarchical self-assembly of nanoscale components to achieve specifically desired three-dimensional structures and their associated functionalities. Analysis of these processes in a biomolecular system reveals a previously unanticapated pathway for the genetically encoded control of hierarchical assembly of nanoscale components and the resultant emergence of complex behaviors. (C) 2008 Elsevier Ltd. All rights reserved.