Structural highlights
Function
T2FA_HUMAN TFIIF is a general transcription initiation factor that binds to RNA polymerase II and helps to recruit it to the initiation complex in collaboration with TFIIB. It promotes transcription elongation.[1]
Publication Abstract from PubMed
RNA polymerase II-mediated eukaryotic transcription starts with the assembly of the preinitiation complex (PIC) on core promoters. The +1 nucleosome is well positioned about 40 base pairs downstream of the transcription start site (TSS) and is commonly known as a barrier of transcription. The +1 nucleosome-bound PIC-Mediator structures show that PIC-Mediator prefers binding to T40N nucleosome located 40 base pairs downstream of TSS and contacts T50N but not the T70N nucleosome. The nucleosome facilitates the organization of PIC-Mediator on the promoter by binding TFIIH subunit p52 and Mediator subunits MED19 and MED26 and may contribute to transcription initiation. PIC-Mediator exhibits multiple nucleosome-binding patterns, supporting a structural role of the +1 nucleosome in the coordination of PIC-Mediator assembly. Our study reveals the molecular mechanism of PIC-Mediator organization on chromatin and underscores the significance of the +1 nucleosome in regulating transcription initiation.
Structures of +1 nucleosome-bound PIC-Mediator complex.,Chen X, Wang X, Liu W, Ren Y, Qu X, Li J, Yin X, Xu Y Science. 2022 Oct 7;378(6615):62-68. doi: 10.1126/science.abn8131. Epub 2022 Oct , 6. PMID:36201575[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Rossignol M, Keriel A, Staub A, Egly JM. Kinase activity and phosphorylation of the largest subunit of TFIIF transcription factor. J Biol Chem. 1999 Aug 6;274(32):22387-92. PMID:10428810
- ↑ Chen X, Wang X, Liu W, Ren Y, Qu X, Li J, Yin X, Xu Y. Structures of +1 nucleosome-bound PIC-Mediator complex. Science. 2022 Oct 7;378(6615):62-68. doi: 10.1126/science.abn8131. Epub 2022 Oct , 6. PMID:36201575 doi:http://dx.doi.org/10.1126/science.abn8131
