Solution structure of the C-terminal domain of TFIIH P44 subunit reveals a novel type of C4C4 ring domain involved in protein-protein interactions.
Kellenberger E, Dominguez C, Fribourg S, Wasielewski E, Moras D, Poterszman A, Boelens R, Kieffer B. J Biol Chem. 2005 May 27; 280(21):20785-92. Epub 2005 Mar 24.