A transcription reinitiation intermediate that is stabilized by activator

High levels of gene transcription by RNA polymerase II depend on high rates of transcription initiation and reinitiation. Initiation requires recruitment of the complete transcription

machinery to a promoter, a process facilitated by activators and chromatin remodelling factors. Reinitiation probably occurs through a different pathway1. After initiation, a subset of the

transcription machinery remains at the promoter, forming a platform for assembly of a second transcription complex2,3,4. Here we describe the isolation of a reinitiation intermediate that

includes transcription factors TFIID, TFIIA, TFIIH, TFIIE and Mediator. This intermediate can act as a scaffold for formation of a functional reinitiation complex. Formation of this scaffold

is dependent on ATP and TFIIH. The scaffold is stabilized in the presence of the activator Gal4–VP16, but not Gal4–AH, suggesting a new role for some activators and Mediator in promoting

high levels of transcription.

We thank members of the Hahn and Reeder laboratories for helpful discussions, and A. Krumm, S. Parkhurst and R. Reeder for comments on the manuscript. We also thank L. Prakash for providing

the Rad3ts strain, M. Solomon for providing the Kin28ts strain, D. Reinberg for TFIIE antibodies and H. Sakurai for providing the Tfa1ts strain and antibodies to Gal11. This work was

supported by grants from the NIH to S.H. and an NIH training grant to N.Y. S.H. is an associate investigator of the Howard Hughes Medical Institute.

Present address: Institute for Systems Biology, Seattle, Washington, 98105, USA

Division of Basic Sciences, The Fred Hutchinson Cancer Research Center, and Molecular and Cellular Biology Program, University of Washington, Seattle, 98109, Washington , USA

The Howard Hughes Medical Institute , Seattle, 98109, Washington, USA

Anyone you share the following link with will be able to read this content: