7o4j
From Proteopedia
Yeast RNA polymerase II transcription pre-initiation complex (consensus)
Structural highlights
FunctionRPAB2_YEAST 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. Pol II is the central component of the basal RNA polymerase II transcription machinery. Pols are composed of mobile elements that move relative to each other. In Pol II, RPB6 is part of the clamp element and togther with parts of RPB1 and RPB2 forms a pocket to which the RPB4-RPB7 subcomplex binds (By similarity). Publication Abstract from PubMedTranscription initiation requires assembly of the RNA polymerase II (Pol II) pre-initiation complex (PIC) and opening of promoter DNA. Here, we present the long-sought high-resolution structure of the yeast PIC and define the mechanism of initial DNA opening. We trap the PIC in an intermediate state that contains half a turn of open DNA located 30-35 base pairs downstream of the TATA box. The initially opened DNA region is flanked and stabilized by the polymerase "clamp head loop" and the TFIIF "charged region" that both contribute to promoter-initiated transcription. TFIIE facilitates initiation by buttressing the clamp head loop and by regulating the TFIIH translocase. The initial DNA bubble is then extended in the upstream direction, leading to the open promoter complex and enabling start-site scanning and RNA synthesis. This unique mechanism of DNA opening may permit more intricate regulation than in the Pol I and Pol III systems. Structure of RNA polymerase II pre-initiation complex at 2.9 A defines initial DNA opening.,Schilbach S, Aibara S, Dienemann C, Grabbe F, Cramer P Cell. 2021 Jul 22;184(15):4064-4072.e28. doi: 10.1016/j.cell.2021.05.012. Epub , 2021 Jun 15. PMID:34133942[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
