Fig. 2.

Models and observed structural interactions for human Mediator. (A-C) Model and observed structural interaction diagram for MedMiddle and the CAK module of TFIIH (A), MedHead (B), and MedTail (C). The N-terminus of the scaffold subunit Med14 extends the length of MedMiddle. Putative density for Med1 and Med26 are shown and colored purple and dark blue, respectively. The C-terminus of Med14 forms extensive interactions with MedHead. MedTail also interacts with the C-terminus of Med14, but on the opposite face. Portions for which models were built are shown in color; unmodeled sections are shown in gray. Known domains are shown with a light-to-dark (top-to-bottom) gradient. Everything else is shown with a dark-to-light gradient. Models colored as in Fig. 1.