Structural highlights
Function
A0A4X1ULF2_PIG DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Common component of RNA polymerases I, II and III which synthesize ribosomal RNA precursors, mRNA precursors and many functional non-coding RNAs, and small RNAs, such as 5S rRNA and tRNAs, respectively.[PIRNR:PIRNR000779]
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[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ 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
