Structure of RapA, a Swi2/Snf2 protein that recycles RNA polymerase during transcription (Shaw, Gan, Zhou, Zhi, Subburaman, Zhang, Joachimiak, Jin and Ji. Structure 2008; 16:1417-1427. Full Text). On the top, the domain organization of the protein is shown with boundaries. In the middle, the domain arrangement of the protein is shown schematically by two views related to each other by a 180-degree rotation around the vertical axis. On the left,right and bottom, the folds of individual domains and a cluster of four domains (1A, 1B, 2A and 2B, which form the ATPase core of the enzyme) are illustrated.