The cyclin-dependent kinase 8 module sterically blocks Mediator interactions with RNA polymerase II.

Hans Elmlund, Vera Baraznenok, Martin Lindahl, Camilla O Samuelsen, Philip J B Koeck, Steen Holmberg, Hans Hebert, Claes M Gustafsson

Department of Biosciences and Nutrition, Karolinska Institutet and School of Technology and Health, Royal Institute of Technology, Novum, SE-141 87 Huddinge, Sweden.

Proceedings of the National Academy of Sciences of the United States of America 2006 Oct 24

filter terms:

CDK8 (cyclin-dependent kinase 8), along with CycC, Med12, and Med13, form a repressive module (the Cdk8 module) that prevents RNA polymerase II (pol II) interactions with Mediator. Here, we report that the ability of the Cdk8 module to prevent pol II interactions is independent of the Cdk8-dependent kinase activity. We use electron microscopy and single-particle reconstruction to demonstrate that the Cdk8 module forms a distinct structural entity that binds to the head and middle region of Mediator, thereby sterically blocking interactions with pol II.

Citation

Hans Elmlund, Vera Baraznenok, Martin Lindahl, Camilla O Samuelsen, Philip J B Koeck, Steen Holmberg, Hans Hebert, Claes M Gustafsson. The cyclin-dependent kinase 8 module sterically blocks Mediator interactions with RNA polymerase II. Proceedings of the National Academy of Sciences of the United States of America. 2006 Oct 24;103(43):15788-93